You can't compare people generation to generation because skill and knowledge is passed down over time and overall increases over time.
The only way too compare players is to their contemporaries. Then you look at how much of a gap there was between them.
Then you compare current players and the gap in skill and talent between them and their contemporaries.
For example what is the closest average to Bradman's in his era and what is the closest average to Tendulkar or Vivs in his era.
Then you get a clear understanding of what it means to be great.
And who is going to ensure that the modern day greats are competing with the same Amateur level batsmen as Bradman did and only from 2 countries ? This is nothing new you are saying and has been thoroughly dissected and answered right here on this page.
So now one of 2 things will happen:
1. You will pretend that Bradmans peers were outstanding cricketers just like any modern day cricketer
2. Or you will run away from this thread.
Otherwise every single aspect of Bradman and his dominance has been meticulously dissected and addressed.