Why are men

I met this guy off of bumble let’s call him Ryan. Well we matched back in May but I wasn’t so interested in him I just left a compliment on messages to him. I didn’t expect it to go anywhere. Just thought he was cute. Well he messaged me back and we ended up talking for 2-3 weeks and meeting up about 3 times. I actually enjoyed him as a person once I met him. He was super romantic and sweet. Well I could tell he wasn’t replying as much and would actually not snap me back but kept snapping other people. No big deal I just left it alone. Well a week goes by and I snapped like hey wanna meet up? Well he replied and was like things have to change, I’m in a committed relationship now. So I said okay, understandable thanks for letting me know. I left him alone afterwards. Now a week later, he messaged me and he asked to exchange sexual videos. I wasn’t having that, I replied and said “I thought you were in a committed relationship. I don’t think that’s a good idea and I feel uncomfortable doing that.” He left me on read 😂 why do people think they can do this?