Our Mishna on Amud Aleph discusses a fundamental three-way dispute regarding the permissibility of divorce:

בֵּית שַׁמַּאי אוֹמְרִים, לֹא יְגָרֵשׁ אָדָם אֶת אִשְׁתּוֹ אֶלָּא אִם כֵּן מָצָא בָהּ דְּבַר עֶרְוָה, שֶׁנֶּאֱמַר (דברים כד), כִּי מָצָא בָהּ עֶרְוַת דָּבָר. וּבֵית הִלֵּל אוֹמְרִים, אֲפִלּוּ הִקְדִּיחָה תַבְשִׁילוֹ, שֶׁנֶּאֱמַר (שם), כִּי מָצָא בָהּ עֶרְוַת דָּבָר. רַבִּי עֲקִיבָא אוֹמֵר, אֲפִלּוּ מָצָא אַחֶרֶת נָאָה הֵימֶנָּה, שֶׁנֶּאֱמַר (שם), וְהָיָה אִם לֹא תִמְצָא חֵן בְּעֵינָיו:

Beis Shammai says: A man may not divorce his wife unless he finds strong evidence of her having committed adultery, as it is stated: “Because he has found some unseemly matter [ervat davar] in her, and he writes her a scroll of severance” (Deuteronomy 24:1). Beis Hillel says: He may divorce her even due to a minor issue, e.g., because she burned or over-salted his dish, as it is stated: “Because he has found some unseemly matter in her,” meaning that he found any type of shortcoming in her. Rabbi Akiva says: He may divorce her even if he found another woman who is better looking than her and wishes to marry her, as it is stated in that verse: “And it comes to pass, if she finds no favor in his eyes” (Deuteronomy 24:1).

Rabbi Akiva may seems cavalier regarding divorce, but he is merely discussing what is technically permitted. This is not a statement about what is morally proper. There is a concept in halakha known as נבל ברשות התורה, a disgusting person who acts in accordance with the Torah (Ramban Vayikra 19:2 comments on this at length).

Additionally, there seems to be a particular investment and sensitivity that Rabbi Akiva has regarding feminine beauty. We find the following dispute between Rabbi Akiva and an earlier generation of Sages in Gemara (Shabbos 64b):

זְקֵנִים הָרִאשׁוֹנִים אָמְרוּ שֶׁלֹּא תִּכְחוֹל וְלֹא תִּפְקוֹס וְלֹא תִּתְקַשֵּׁט בְּבִגְדֵי צִבְעוֹנִין, עַד שֶׁבָּא רַבִּי עֲקִיבָא וְלִימֵּד: אִם כֵּן — אַתָּה מְגַנָּהּ עַל בַּעְלָהּ, וְנִמְצָא בַּעְלָהּ מְגָרְשָׁהּ. אֶלָּא מַה תַּלְמוּד לוֹמַר: ״וְהַדָּוָה בְּנִדָּתָהּ״ — בְּנִדָּתָהּ תְּהֵא עַד שֶׁתָּבֹא בַּמַּיִם.

Regarding the verse: “And of her that is sick in her menstrual status [niddata]” (Leviticus 15:33), the Elders of the early generations said that this verse comes to teach us that the menstruating woman should be distanced from her husband in all senses, like a person ostracized [menudeh] by the Sages. This includes that she may not paint her eyes blue, and she may not rouge [pokeset] her face, and she may not adorn herself with colorful clothing. Until Rabbi Akiva came and taught: If you do so, you are making her unappealing to her husband, and her husband will consequently divorce her. Therefore, extreme strictures should not be instituted. Rather, what is the meaning of that which the verse states: “And of her that is sick in her menstrual status”? She shall remain prohibited in her menstrual status even after the flow of blood has stopped until she immerses in the water of a ritual bath.

Ben Yehoyada (ibid) makes a bold assertion (I am printing the Hebrew, because it is so sensitive so don’t take my translation alone):

דרבי עקיבה היה תחלתו עני שהיה כמה שנים בתחלת ימיו מסוג העניים, ואחר כך בא ונכנס עם סוג העשירים, ומצינו אחר שנתעשר היה מכבד את אשתו בתכשיטין יקרים מה שלא עשו זאת שאר חכמים, כי אפילו אשתו של רבן גמליאל שהיה נשיא ועשיר גדול נתקנאת ממנה, ואמרה לבעלה אתה נשיא וגדול איך לא תעשה לי כמו שעושה רבי עקיבה לאשתו?! ועוד אמרו רבותינו ז"ל דאמרו לו תלמידיו רבינו ביישתנו במה שאתה עושה כל כך לאשתך! ומאחר שהיה נותן כבוד לנשים לכך שם על לבו לדרוש ולתת טעם בתכשיט הנשים גם בימי נדתה, כי התכשיטין הם כבוד האשה. וזה שאמר עַד שֶׁבָּא בסוג העשירים שאז היה נזהר בכבוד הנשים, ואז לימד הלכה זו הנותנת כבוד ויקר

Rabbi Akiva began his life as a poor man, spending several years in the beginning of his days in a state of poverty. Later, he became wealthy and entered the ranks of the rich. We find that after he became wealthy, he honored his wife with expensive jewelry, something that other sages did not do. Even the wife of Rabban Gamliel, who was a prince and very wealthy, was jealous of her and said to her husband, 'You are a prince and a great man, how come you don't treat me as Rabbi Akiva treats his wife?!' Our rabbis of blessed memory also said that his students rebuked him, saying, 'Our master, you shame us with what you do to your wife!' Since he showed respect to women by paying attention to the adornment of their jewelry, even during their menstrual period, for jewelry is a woman's honor. And this is why he said that until he became rich, he was not careful about honoring women, but then he learned this law that bestows honor and importance.

(I think Ben Yehoyada never would have written such a thing if he came from an Ashkenazi culture that went through and became reactive to the 19th-century German Jewish reform movement. At that time, the Reformers viewed the rabbis of the Talmud from a so-called historical and biased point of view as creators of the oral law instead of conservators of the oral law. This has left an indelible mark of fear and reaction to anything that smacks of a consideration of subjectivity in the halakhic process.)

I will add an additional interpretation to what Ben Yehoyada says. Since Rabbi Akiva considered finding someone more attractive to be technically grounds for divorce (of course, as we stayed earlier, not necessarily praiseworthy), special attention needed to be made within the practice of halakha to allow women to continue to adorn and beautify themselves during Niddah. Or, perhaps since maintaining beauty was an important value to Rabbi Akiva, it informed both his understanding of the verse in Niddah and also his understanding of its role in marriage. Regardless, Ben Yehoyada’s idea about Rabbi Akiva shows that he believes in some subjectivity in the process of making a rabbinic a halakhic derasha.