I don't know about the counterexamples.
Rifts is a dead letter. When you have to ask your fans to make donations to support your company it's probably not in good shape. There are more people playing 1st edition D&D than there are playing Rifts in New York City.
Likewise, everyone I know who is interested in Vampire, especially OWoD, is interested in it despite the rules. If their rules didn't suck, I think they also wouldn't see their player base dwindling to the point where that company is likely to go under in the next year or two. Even the big cash grab of V20 was met with a resounding "meh" by everyone outside of a very small, hardcore fanbase. I say that from my perspective of being good friends with some of their playtesters.
That being said, I could be totally wrong. I just think a game that is easier to play or run, one that works as advertised, tends to have a lot longer shelf life. Where I define shelf life as being able to push product. Games can be easier and hard in lots of ways, but one way that they can be made hard is what I call landmines. I think most people, optimizers aside, actually aren't that interested in them, and find themselves having to dodge them. Identifying them, and suggesting ways around them, is a service system-minded players, like optimizers, can provide.
This is sort of a tangent, but I also think the tolerance for bad rules in games has gone way down in the past decade or so. Perhaps it's due to the wider availability of small print games, or simply that there are a few decent rules systems out there at present. But, way back in the day when I got into Rifts (and oh god, did I play a lot of Rifts), I knew its rules were terrible. But, it's only real competition was AD&D (sort of terrible rules) and White Wolf. So, it didn't look too bad by comparison. Nowadays, there are lots of options, many of which are pretty good.
Finally, I think 4E, to the extent optimizers were involved in playtesting, drew many of the wrong conclusions. In their desire to standardize things and avoid ... whatever, I don't even know, they bled a lot of the color and flexibility out of the game.