You know what else the 1930s had? The best batsman of all time.
So, y'know, while the pace bowlers may have been slightly worse in that decade (Australia's were, but England's certainly weren't) and the spinners might have been terrible (they weren't), and the pitches might have been slightly flatter (no quarrel with that point from me), you have to respect that there's another factor in the performances of bowlers that you've continually disregarded -- batsmen. Nice little false cause fallacy, really.
You call it "known cricket history" that bowling got worse in the early 2000s -- a statement you're inferring from the character of (bat-dominated) cricket we've seen since 2000ish. Given the relationship between batsmen and bowlers, I could argue that batsmen simply got better in the early 2000s, bringing about exactly the same results we witnessed. And I have exactly the same amount of evidence you do (i.e. none).
Did bowlers inexplicably turn to **** in the 2000s, making batsmen look better than they were? Or did batsmen inexplicably become so good that they devalue their own achievements by making us class everyone as a "poor attack" because they didn't average the same as somebody playing in 1950? The answer is we can't really tell, and any analysis we do becomes necessarily qualitative. Bowling averages don't occur in a batsman-less vacuum.
You are claiming that your opinions are facts. They are not.
Well while I don't agree with you, respect as moderator/CW staff member for willing to discuss your POV unlike others.
I'm not sure what exactly your trying to say by referring to Bradman to be fair.
However in the 1930s and actually entire 1900-1939 there was not other good fast bowling attacks other than Bodyline 1932 lead by Larwood & AUS Jack Gregory/Tim McDonald (although some historians speak favourable of early Windies pair Constantine/Martindale). Teams started to have a regular presence 80mph/90pm as new ball bowlers until after WW2 with emergence of Lindwall/Miller.
Back in 1900-1939 of sticky wickets, teams were heavily spin based like a sub-continent team or had extinct medium pace bowlers of the Maurice Tate, Alec Bedser, Amar Singh, Bob Appelyard, Monty Noble etc ilk leading their bowling attacks.
From the 50s to the 90s many teams had regular pace attacks in large proliferation & I won't insult your intelligence & suggest you don't know who those were.
When the Donald/Pollock, Wasim/Waqar, Gough/Caddick, Ambrose/Walsh, hell even Srinath/Prasad for India & Streak led Zimbabwe all declined or retired at the end of 1990s into 2000s - from 2000-2005/06 only AUS had a consistently good pace/general attack in the formative years of the 2000s. Only other time teams faced challenging bowling was a trip to IND/SRI facing Kumble/Harbhajan, Vaas/Murali.
IND was crap. NZ entire 2000s era of talented fast-bowlers were whipped out due to injury & were a crap attack led by Chris Martin most of time, Akhtar was injured more than he played & PAK were crap most of time until Inzamam took over & Mohammad Asif arrived, IND was crap, SA were poor until Ntini peaked & Steyn emerged.
ENG Ashes 2005 attack which started in WI 04, was the only other pace attack of those 5-6 years that was solid for a long period of time.
That clearly made the 2000s era the worst time for the presence of good pace attacks since the 1900-1939 period.
This is a well established and its not even my opinion hardly. You talk about facts - well a long time ago people already proved it:
http://www.espncricinfo.com/decadereview2009/content/story/442008.html
"A time to loot and plunder.Aided by fat bats, flat pitches and the absence of menacing bowlers, batsmen made merry in the 2000s, setting new records and devaluing Test run-making in the process - Peter Roebuck"
http://www.espncricinfo.com/decadereview2009/content/story/441892.html
"Why 55 is the new 50. Numbers indicate that the noughties was the best decade for batting in a long, long time - S Rajesh"
I don't buy that batsman have gotten better. T20 cricket has probably made them more aggressive, more innovative with their strokes & yea they take more batting risks than before. But since 2006 more teams have had good fast bowlers & we have a better balance now compared to 2000-2006.
You look at how poorly most teams play the moving ball now worldwide vs these good attacks & that IMO is one the side effects of what the FTB early 2000s era & T20 has done to batters techniques.
AUS batsman historically for eg always had their problems vs spin, but they have never played swing-bowling so badly as batting group in AUS cricketer history as they have been doing since 2009.