I think people are just judging him as a rugby player.
It doesn't matter about levels of experience, he's player out there starting at 12 in the top level European rugby competition, and his performances will be judged on that.
No one is judging him harshly because he came from League - unlike League, there is very very little negativity towards the other code from Union fans.
If the main excuse given up is "Well he's really new, he's obviously not going to be at that standard yet" then he shouldn't be playing at that standard yet, simple as. If Bath hadn't played him in Europe nobody would've batted an eyelid, as it was expected that he'd be playing 'A' League and LV= cup at first.
But then Bruce Craig paid a ridiculous amount for him, so he's going to want him out there - like GN10 has said, nobody has any issues with Burgess at all, it's more with the Bath coaching staff who have rushed him into starting, at a position that they don't see him playing, and that he doesn't see himself playing.
He's playing about as well as I expected, to be honest. Defences are terrified of him, so they man mark him with 2 or 3 players everytime the ball comes near him, which creates a lot of space elsewhere. To be honest, if they wanted him in the centres, I think they should've brought him through as a 13 (a Manu type player), as Bath really missed Eastmond, and a Ford/Eastmond combo would be able to exploit the gaps that Sam's presence creates.