Why would a man prefer phone sex over the real thing?

I’ve been talking to this guy for about a month now and know he works local and is from my area. We have a few mutual friends but have never met. I saw him on a dating site and he said hello.
We were chatting and to my surprise he suggested video sex. It’s not something I’ve ever done and am a little unsure about it.
We have sent pics to each other, nothing too raunchy.
I just don’t get why he’s so into this phone sex. I respect that he’s not putting it about but feel like I’m not going to really get much out of it apart from knowing he was turned on but watching me.
Why do men prefer this sort of thing?
Why would a man prefer phone sex over the real thing?
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