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I agree but making a show in which "actors actually look like teenagers" should put more effort into the teenage awkwardness aspect. 
Like yeah, I have no problem with that 25 year old playing a 17 year old character but give the character some sloppy makeup that looks like a teenager just starting to learn how to use it. Where's the mismatched foundation with braces and bright blue eyeshadow? With the special effects makeup we have nowadays, there's no reason teenage characters can't have a fake pimple or two either. Cast short actors and flat-chested actresses, we didn't all finish puberty in our junior year. And why is do none of these characters ever seem to experience inconvenient periods and embarrassing voice cracks? There's more to looking/acting young than being energetic with a youthful face.
Every teenage character looking like a supermodel is much worse than every teenage character being played by a 25 year old if that makes sense
Kid actors usually suck and it's usually some parent-influenced career choice that they won't continue into adulthood anyway. I'll take a decent 20 year old over a 15 year old almost every time. >

Yeah unfortunately the problem is that the shows that feature those "teenagers" are targeted at actual teenagers and it pretty much warps their entire reality of what being a teenager should look like. >

Problem is with casting actual kid actors is they aren't done growing which becomes problematic unless your show is doing time jumps.  Look at Stranger Things where only 2-3 yrs total have elapsed in show time but all the kid actors aged eight years and show it.
The reverse is kinda funny though.  In House of the Dragon they cast a then 20 yr old to play the 14 yr old main character.  Then mid season do a time jump and recast her with a then 28 yr old actress.  Which I just find humorous since the original actress was actually closer to this second age than the one she played.  Why not just keep using her and make her look older with makeup instead of younger. >

Im pretty sure there is also labour laws that are different for anyone under 18 so you can only film for so long so having kids just makes it that much more difficult >

Yeah, sure. Gabrielle Union
 for example doesnt age. Girl was playing 15yo roles while being in her late 20s, and honestly? She could totally pull it