Sure. What I mean is at 16:9 you're still getting letterboxing (black bars on top + bottom). In addition to that, it's rather silly to think that just because 16:9 is closer to a theatrical ratio that you're going to ever get a cinematic experience sitting 2 feet in front of a 24" monitor. Or 6 feet in front of a 46"+ TV. We optimized all of our devices for viewing DVD content whether it ever made sense or not. Because home theater was where the money was.

4:3 is better because it fits the application better. What are you doing at your computer? Probably work or browsing the web. If you watch YouTube videos then you have a chicken-and-egg issue... YouTube content is 16:9 because that's what your device is (to see what I mean: look at all the vertical videos today... the content follows the device). YouTube/TikTok creators aren't using aspect ratio in an artistic manner because few of these people are even aware that they could have a say in the matter. Unlike say, Kubrick, who deliberately picks a ratio for each of his films. They are using what the prosumer cameras are designed for, which is all 16:9.

The point is: you're getting black bars if you watch theatrical content whether it's 4:3 or 16:9. The width of your computer monitor is a constant. So we lost vertical screen space for what? Nothing, that's what. Slightly less black bars on the top and bottom when we watch a Marvel movie on our desktop computer or laptop.