Apparently not that many, given the extremely small number of audio companies who have actually released CLAP versions compared to VST3. It would be near impossible to list all of the significant developers who HAVEN'T released CLAP versions, but a pretty easy task to list all who have.
And that's what we have here: nebulous claims that VST3 is no good and has hurt some feelings vs. sheer numbers that demonstrate CLAP isn't a viable solution for audio production right now.
Yes, yes, one day CLAP shall unite the realms. It has been prophecised...