Golden Tee PC was released on 333's. I have played the PC version (ebay - $6) on a 200 mhz.
I don't like driving games, so I don't know about them.
Somebody has to buy some of the games sometime, or there won't be any.
IF mame were to completely stop development now, I'd be happy for years and years to come with what is there today. If adding new games risks what we have, then I agree, we sholdn't push it anymore.
I think that some people have already released commercial versions of machines with a mame engine, and it's just disguised. I look for it all the time. I saw a machine being sold by some asians that played 50 games off some small box made in mylaisia. The pacman version booted like mame does. Things like this will stop mame.