There was a long thread on this issue last year, and the majority of the posts saying Alabama would get killed are like this one by Buffalo716: No real evidence offered (other than misinformation), just blanket statements with nothing to back them up.
Fact: All 22 starters on Alabama this year will have a shot in the NFL, and perhaps 15-18 will make NFL rosters. Of those, most will be drafted and there are probably 6-8 who will be first round picks, although not all in 2020. On the 90-man roster, I'd guess that there are 40 or more who will have a very good shot at playing pro football. Unlike NFL teams, Alabama is not limited to one first round pick per year; each recruiting class has probably 4 to 6 future first or second round picks. Clemson and Ohio State aren't far behind.
Miami on the other hand probably has 10 players who wouldn't make most NFL rosters and has a number of guys on their team who probably would not start for Alabama. Robert Foster, for example, was the Bills' best receiver last year and he was a backup at Alabama the previous year.
I think it would be a competitive game and there's a good chance Alabama would win.