I pre-ordered a Switch based on Zelda, and Mario. I also bought it so that I can play games on the couch whenever TV was in use and I can't play. Third Party Support does definitely matter to me, but I think that it was never a question about the console/handheld's power levels being reasonably close to WiiU. Let's be honest, I can't imagine what a PS4 power level handheld would cost. Certainly not $300. But, I like that semi-console level power in a hand held is appealing. I never figured a RE7 would come to it, and never thought it would be possible either.
I do agree with some on here that a RE game would be possible on it, and think that game companies put games out they think there's enough money to be made on regardless of what system it would be on. It's a business after all.
I think 3rd party support would be there if adoption rate is there. Adoption rate is based on a lot of things. I remain hopeful, that there is enough about Switch to attract adopters, and therefore by proxy 3rd party support. What games that would include should be interesting. I wouldn't rule out ground up built RE games.