Who says they are? There's plenty of crap available for Linux. I mentioned Braid because it's a very popular and very good Indie game available on both platforms. I surely wasn't implying that Linux only receives ports of the finest of games.
Also what makes a game "good" is subjective. From the perspective of hours played, Braid isn't very good.
> That doesn't describe the situation well. Linux gaming is for sure a much smaller market than Windows gaming, but not only it's already viable
It is viable for some small developers and for larger developer who are already using tools ported to Linux it can make sense to add support however for the majority of game studios making popular (not necessarily good or bad games) it doesn't make sense.
The market however is viable for everybody, but as I said, if everybody from the Windows gaming market will start releasing games for Linux now, it can actually hurt it, rather than improve it. Gradual growth is better, and it's already happening. Tools wise, the situation is getting much better as well, with all major engines gaining Vulkan support. Common middleware like Umbra 3D also often supports Linux these days.
In way I don't mind that Linux gamers are getting better games on average, because of less mass market mediocrity, but more interesting (usually crowdfunded) releases that are reaching Linux gamers today. However it ties to the next point, of the market size:
> You can say that there are plenty of good games on Linux and everyone should switch but the reality is that the games people want to play are either unavailable or lacking in some way that makes Linux on the desktop a non starter.
That doesn't describe the situation well. Linux gaming is for sure a much smaller market than Windows gaming, but not only it's already viable (as many developers who sell Linux games demonstrate), it's gradually growing. So it's surely not a "non starter" anymore.
However, since it's smaller, having too many games can actually cause a problem, even if it sounds funny. Simply because it will be overcrowded developers wise, and they'll have harder time selling Linux games. So I'd say actually current amount of games healthily corresponds to the rate of Linux gaming growth.