For a long time I found the single biggest difference between them to be:
Even the best TVs had atrocious latency compared to cheap monitors. I don’t really know why this is, but it likely has something to expensive transformations to the video signal to “improve” quality. I have very pricy 1080p Samsung TV from 2013. Even in “Game Mode” I has latency of over 100ms. This enough to be noticeable in just moving a mouse around, let alone gaming.
That has been mostly rectified nowadays. I have an LG C1 (42”) and use it for gaming and work. It has <1ms average latency and just enough pixel density for computer use. It does need a good desk though.
The biggest remaining differences would be:
- TVs tend to have a “smart interface”. This can generally be avoided if you are just switching between inputs.
- TVs tend not to support DisplayPort input.
- TVs tend require large desk stands and are not VESA compatible. You need a large desk to use one as a monitor.
- Very few TVs with high quality panels are available in smaller more pixel dense sizes. I’m imagining this will become less of a problem with a move to 8k.
- TVs tend to have almost unusable colour calibration out of the box. Rtings reviews tends to note how close the displays get to a standard colour profile after calibration. Many can be calibrated to a reasonable level though.
- OLED panels are much more common in TVs.