Tough choice.
I have smart TVs (LGs and Samsungs). But the apps are slow and clunky (mainly because no decent OS running on puny CPUs), and both these TV vendors are dictatorial and constricting in their firmware/updates.
On the other hand, external devices mean yet another blerry remote control and yet another device cluttering up the place, and more fiddliness switching inputs, etc.
I'd prefer a TV that can load a decent operating system that supports discrete apps for the various streaming services, but that's a pipedream...