im not sure a limit solves much

1) it is possible to bypass the limit by signing up more cards. for example, most of my non-US credit cards have limited lounge access, but i still managed to accumulate around 50 passes every year, and this number can be much higher should i desire. in the US, i have CSR, VX and many pp accounts from non-US cards (they can each visit sapphire lounge once a year). so once i maxed out my C1 lounge, i will visit the sapphire lounge, while someone else may do the opposite, and demand stays similar

2) the problem of overpacked lounges is similar to traffic jams. demand fluctuates, and noone will cater for peak demand, so lounges in highly trafficked airports during peak hours are still going to be overwhelmed

im not saying it wont help, but im not sure it will improve the situation much