Can’t answer question directly. Just, when I was your age, there was so much I needed to learn. Every person takes time to figure things out, overcome shortcomings, work thru stuff.
At 21, lot to figure out, discover, learn. For me, cuz childhood abuse, trauma, autism, I was a mess. No idea how to have healthy relationships, positive communication, etc.
So, could be your dude is just young, figuring stuff out. Or could be something else. Only way to know is to ask, talk about it. No assumptions, no judgment. Communication is key.
Might be useful to research how to communicate effectively. How to talk about stuff in not about criticize, instead seeing other person’s viewpoint, meeting half way. Problem is, other person may not want to or be able to.
You’re doing good, asking questions. Keep doing that, and good luck.