I have the exact same issue. I was trying to update the Shop Channel without updating to 4.3 (I was on 4.2U) and after a reboot, I no longer get a video signal on tv.
I had BootMii installed as boot1, I believe, I'm not sure.
The disc led flashes only once, if that's any help.
When I power on...
I haven't played my Switch n a month or so, just been playing Xbox, and just picked to play lil and Damn that A and B, X and Y being reversed always gets me.
I agree Tears is great. I even played thru it completely twice. I've been hooked on playing thru Fallout 4 again though, after they released the next gen version for Series S/X. Is pretty cool update.
because I already got burned out with breath of the wild, which for the most part is essentially the same game, and then again with master mode, which doesn't work as a new game plus (that always felt bizarre to me)