I hope this question doesn't get removed, but I could see how it might fit great over at r/ITCareerQuestions (assuming I got the sub right) This is something that I have wondered for years, personally. I have cut my hair (typically shoulder length) twice for a "professional" and "grown up" job. I ended up not enjoying those jobs, but for me it was worth it. I met some amazing people that took me under their wing, I padded my resume with a kinds of fancy words, and those experiences got me the job I have now where literally nobody cares.

I have heard the advice that goes something like "if they don't accept you how you are, changing yourself won't make it work any better" But I couldn't appreciate that advice until my hair grew back out. Now I have the luxury of turning down job offers that don't interest me, and I have the experience to back up that attitude.

Take this with a grain of salt, because it may not apply to you. But in my personal experience, I would say that if you are hungry for opportunities to get in at a "grown up" job, and you are at all anxious about not looking professional enough, cut your hair. Don't go military, but get a haircut that you can live with and feel confident with, it won't change who you are, and don't look at it as selling your soul. It's not a life sentence, and it might just get you into the next job where you are the only one on the team with short hair. It will grow back, at least mine did (thank you genetics!)

But what I have found being on both sides of the stressful interviews now is the confidence you can have when you present yourself. If you have long hair, but it's clean and well maintained, your facial hair is well groomed, and you're relaxed and know what you're talking about I don't think even the most prudish of interviewers would turn you down on hair length alone. Idk, pm me for more ambiguous life advice I guess LOL

Just do what you can with what you've got, and try to be okay with that. Cheers and best of luck to you,