NewPipe stops working whenever Google updates YouTube with a breaking change that NewPipe needs to integrate then, e. g. renaming parameters, changing URLs and the like.
NewPipe has been steadily working for years, with the expected interrupts as they have to play catch up with YouTube. That typically only lasts a few days, sometimes hours, though.
It's been working for me most of the time. Tends to break when Google breaks something, but gets fixed pretty fast. For me it has been working for a couple of weeks after the last update. On TV I use SmartTube, and it has been incredibly solid.