Why would devs back another underpowered Nintendo console?

I ask this question sincerely because certains things don't add up.

Bethesda shitpiled on the WiiU. No publisher was louder about the mistakes made with the WiiU than Bethesda. Then the Switch they said they'd support it 'If it was powerful enough'. Now cue the part where they entangle themselves with the Switch reveal after basically never supporting a Nintendo console before.

We heard rumors in the past that Switch would be 'just below' the Xbox One in power in some form. That would be good enough to run the likes of NBA2K, Skyrim remaster and probably even the rumored Dark Souls 3 port. But if reports of an underclocked Tegra X1 in the retail unit are to be believed, then Switch only tops out to 400 gflops to the Xbox Ones 1.3/1.4. That's less than half the power of Xbox One and like - and a tenth of PS4 Pro at 4.2 teraflops.

So why would publishers like these appear to give more enthusiastic support to the Switch than they did with WiiU? Especially when the power gulf between the Switch and it's new competitors PS4 Pro and Xbox Scorpio is even bigger than between WiiU and base PS4/X1?

The only logical explanations are:
1. Switch is probably more powerful than currently believed
2. All 3rd parties are in on some ruse to build up hype for the Switch only to disappoint us more than we ever were with the WiiU

they backed the wii, because it sold, the ds and some the 3ds, because it sold.
So logic and history tells us if the console sells, they will back it.

Also some obvious ports, from telltale games and yooka layli and stuff, will happen. A lot of japanese games which are ports/upgrades from vita to PS4 should get a NX port.

its going to be a coin flip, people seem less excited then the wii but more excited then the WiiU so it will sell somewhere in between, if its on the high end, many games will come to the NX, sports games, some lighter third party games, else, nintendo has to quit this underpowered console strategy.

They wont. Most of them, like Fromsoftware and Bethesda are only gonna port old games to the console, so strictly speaking Nintendo can claim they have their support, even tho they are only going to port old game or make some shitty spinoff like Squareenix does

1) nintendo went around with bags of money, and baskets full of cookies.

2) the reason they didnt like the Wii U, was the concept (split gameing, between 2 screens ect), and they like this concept better.

3) maybe they think this has a chance of actually selling well (unlike the Wii U).

Because they get a working IOS / Android hardware compatible port for free. If it runs on the Switch hardware, there will be almost no effort to release it on mobile devices. And also porting existing mobile games to switch is easy too.

Porting Skyrim to Switch alone is not worth the cost and effort at all because sales expectations are very low.
But porting Skyrim to Switch and also releasing it on IOS / Android Appstores will create a lot of revenue and is worth the effort.

There would be a certain appeal of farming out some IPs to companies like From Software and Bethesda for mature IPs like Metroid, Eternal Darkness or something else like that.

Most likely the reason.

Maybe it really is just that easy to develop for. Maybe they're working on Nintendo franchises and crossover deals. Maybe they genuinely believe that portability is a console-selling feature and their games will have a home regardless of how inferior the ports are. Maybe Nintendo showed them software that will help with their audience problem. Maybe Nintendo is making lucrative marketing deals with them. Maybe games nowadays really are that scalable. Maybe it's more powerful than the clock speeds have lead people to believe. Maybe I'm talking out of my behind.

Mobile is still a race to the bottom in terms of pricing though. Have you seen the outrage over $10 for Super Mario Run?