It does certainly get more difficult during college or work, I won't lie. Grinding solves and memorizing tons of algs becomes somewhat less feasible, but that doesn't mean you can't still improve--you just have to prioritize other things. I actually returned to cubing in the middle of college and got faster than I'd ever been before. I grind solves occasionally, but I also often go days without practicing.
It's better to complete the things you NEED to succeed in before shifting your energy to cubing. If your priorities are in line, you can spend time doing things you enjoy with deeper mindfulness, and your practice sessions will be more meaningful. Competitions are a huge social outlet for me too, so attending those is simply a component of my free weekends.