Smart[er] TV

Smart TV has a) built-in apps, such as Netflix and Amazon Prime Video, and b) streams shows via Internet connection, either Ethernet or Wi-Fi.

Dumb TV has neither built-in apps nor Internet connection.

Streaming player, such as Roku, Amazon Fire TV, and Apple TV, have apps and Internet connection.

dumb TV + streaming player = smart[er] TV

Streaming players keep up to date, work better than smart TV apps, usually better Internet connection, and easier to replace than entire TV if/when necessary.

Roku Ultra solves all streaming problems. Three of note:
1. Netflix stopped working on older smart TV. Installed Roku Ultra instead of replacing TV.
2. Amazon Fire TV would not stream certain Amazon Prime Video shows. (I know, right?!) Installed Roku and updated Amazon app.
3. Apple TV did not have Amazon Prime Video app until recently. Roku has always had it.

Dumb TV has same audio and video as smart TV so you can connect cable TV, streaming player, Sonos, DVD player, even surround sound with audio video receiver for full movie experience.

Dumb TV evolved from security camera monitor so has not caught up with the latest smart TV picture technology such as OLED or curved screen. You can use streaming player with smart TV effectively ignoring its apps.