I imagine Bradman would take the biggest hit, and would thus go from being 45 points ahead of the rest of them to merely 40 points better.
Agreed entirely. Actually there should have been a 'none of them' option.
Hobbs faced really tough conditions, he was a real champion on sticky dogs.
Sobers faced some great attacks (the English attack of his time is among the ATG bowling attacks, the Aussie attack was very very good too - and the South African attack of his time was great and very very underrated).
Viv Richards faced some great fast bowlers, though he didn't have to face the fearsome foursome with whom he played.
Sachin Tendulkar played on two different eras. The 90s decade was quite possibly the most difficult decade for a batsman among the last 8 decades. Just like the 70s and the 80s, 90s decade was full of champion fast bowlers - Ambrose, McGrath, Wasim, Waqar, Donald, Pollock, Walsh. But unlike the 70s and the 80s, 90s decade had two all-time great spinners in Warne and Murali. On the other hand, his last 10 years were comparable to Bradman's in terms of difficulty as a whole. (Yes, Bradman faced relatively tough conditions and relatively easier opponents but as a whole the difficulty was like the 2000s.) In this decade, he faced some great bowlers like McGrath, Steyn, Warne, Murali too but the overall quality of bowling was in no way comparable to the 90s.
Bradman faced some superb English attacks. But all other teams he faced were either minnows or just out of the 'minnow' tag. But the greatness of Bradman lies in the fact that he dominated the English attacks of his time like anything. Yes, in his time there were some sticky dogs too, but batting averages in those days are comparable to batting averages in the 2000s.
So yes, in essence what 'The Sean' is saying is true. If Bradman's average is to be adjusted for era and opposition, it'll become 96.09 or something. Big deal!