While there's no single definitive answer, here are some potential reasons why programmers might use anime profile pictures:
Shared Interests: Some suggest a correlation between programmers and geek culture, where anime falls as a common interest.
Self-Expression: People may use anime profile pictures simply because they like them more than their own photos. Anime graphics are considered art, and software engineers may appreciate the successful use of software in creating them.
Confidence Boost: Some individuals feel that using anime profile pictures increases their self-confidence.
Distraction Reduction: Switching to an anime profile picture has been reported to decrease distractions and boost productivity for some.
Humor and Rebellion: After criticism of a developer using an anime picture on LinkedIn, many devs started using anime characters as their profile pictures.
Anonymity: Anime profile pictures can provide a degree of anonymity online.
Trolling: Some may use anime profile pictures to provoke reactions or troll others.
Waifu/Husbandos: Some may feel it increases quality because there is a waifu / husbu damage bonus.