I bought some complete series in DVD in the past but, even putting aside the inconvenience of having to manage discs in the player, there's the quality issue.
I got my 1080p copies on the high seas and that's just a whole different experience.
There's _a lot_ of stuff that has only ever been available in SD (or equivalent). Some of it was shot on film that could maybe be remastered, but that costs money. Some of the older/less popular stuff wouldn't be profitable if it was remastered (assuming remastering is even possible).
> even putting aside the inconvenience of having to manage discs in the player
You're allowed to rip media that you bought