It's not comparing their connection to your quote: 'shitty', connection, it's comparing their connection with and without a VPN.
All VPNs add on delay - and the blatantly obvious: someone connecting with a high delay is bad for any pool.
Assuming a VPN is only going to add a tiny delay to their current connection, sounds like you've never looked at how a VPN performs, only been a 'typical user' of VPNs and never had to care about the performance.

Relevant: on my pool the average pool wide stale rate is 0.19% i.e. 99.81% diff of shares are not stale.
That also includes the biggest connection I have from inside china that chooses to connect direct to West-USA through the GFW.

You seem to have some idea that adding %'s here and there and elsewhere don't matter.
I can certainly say I am glad you don't mine on my pool with your past comments about not caring about finding blocks, and not caring about losing some % of your mining to a firmware, and now telling people it doesn't matter if they lose some % to a slower connection, and as long as they have a lot of money they'll always do the best thing.

Yes the world is full of "I don't care as long as I get money" but I prefer to point out what is best to do, not what is mediocre.