But I was also talking about some fanboys
SDF is unique among popular internet forums in the broad quality of its userbase. There are very few "fanboys" here - especially among the pro-China crowd. Certainly far fewer than you would find in a typical defense forum like BR and f-16.net. If there are any fanboys I've encountered it's among the pro-America crowd who believe in American invulnerability and the occasional Indian troll, but they are relatively few and the moderators ensure that they don't step too far out of line.
the 50k ton battlecruiser
News to me. I've never seen any discussion here about a 50k ton battlecruiser. The closest I can remember is some submersible arsenal ship a prominent ailing naval designer once doodled.
launch before end of 2021
A Q42021-Q12022 launch window is perfectly reasonable for 003. I would grant that 2021 is on the optimistic side, but it's a reasonable estimate and certainly nothing like claiming that 003 is nuclear-powered when we have credible rumours going back years that it would be conventionally powered.
Also overestimations about production numbers are really annoying, just taking maximum rate and extrapolating from that and so on.
Would you prefer underestimations? If so, you must be pretty satisfied because underestimating China is a religious stricture in the English-speaking world. It's a fact that observers in the Anglosphere consistently underestimate the PLA along every dimension - for example, I remember watching think tank panels where participants "debated" whether China would ever build an aircraft carrier, or whether it would even build ships larger than the Type 22. It was a perfectly respectable position to hold that the PLAN would be a somewhat larger IRGC navy.
China's monstrous shipbuilding capability is a fact, the number of warships it launched in the last few years attests to that. The new Bohai submarine yard has the capacity to build 20 SSNs simultaneously*, that's also just a fact. So skeptics should ask themselves whether what they're calling "overestimations" are really that.
*I want to pre-empt any pedantry about the 20 SSN statement along the lines of "but it would build SSBNs as well", etc. The Bohai shipyard can simultaneously construct
x SSBNs and 20 - 4
x SSNs for any
x in {0, 1, 2, 3}.