"As a general rule" I think TV is fine for kids. 

I suppose it depends on what you/they watch. My kids were able to learn lots from TV and still do.

Quite frankly I'd rather they watched a myriad of different types of shows on TV (from good to bad) than the garbage they are exposed to on the nternet via YouTube or by sitting down for a whole day of "marathon" TV that they kids like to now by watching a whole season of something in a sitting.