A lot of people report the same experience, so you shouldn't think it's something wrong with you.
As for the reasoning, I don't know. It's interesting that chess.com chose to do it this way. I think it was a conscious decision to make the site more attractive to newcomers... but the exact reasoning I'm not sure. Maybe because some competitor sites have higher ratings, and also the tendency of new players to overestimate themselves. If a new player was being beaten up by very low rated bots that could be discouraging, and they'd go play somewhere else.
I'm able to defeat bots at the 1300 level on white and black as well as constantly winning against 1000 to 1200 bots. Do the people I face just have deflated ELOs?