Yea, I don't get the Obama comparison. The attacks on her were vicious and non-stop.
Melania has been largely left alone, probably because she is mostly absent in terms of doing much of anything that the public sees. This film is getting attention because a) it's apparently pretty bad and b) Bezos/Amazon paid a lot of money for it, which makes people speculate the reasoning behind that spend.
That said, I'm not a fan of the stuff that makes sexual references about her. I also never found the weekly cheerleaders pics that folks used to post next door to be much fun either, so maybe I'm just a stick in the mud.