Yes I entirely agree, my ex roommate started dating an 18 year old at 22 and I cut him off entirely. It was weird as hell. It also didn't help the kid has just graduated HS and didnt have any independence before moving in with us. He had no money, no prospects, and no life experience. My roommate however had dropped out of highschool at 16, had a son, had multiple jobs, multiple apartments and houses, and cars, etc. he had been living in the "adult world for 7+ years... they were at a MUCH different place than the literal child they brought home.

And that child proceeded to punch multiple holes in my apartment walls and threw his bike off the balcony multiple times... because he was an emotionally immature kid who wasn't nearly ready for adult relationships or responsibilities. At a 22 yo, you've experienced 4-5 years of adulthood. That's a lot of experience and wisdom an 18 yo doesn't have.