I can see why Waitiit, from his perspective, did it even though I feel like it was a big waste of characters but Waititi always struck me as someone who probably didn't read much older comics beyond aesthetics and visuals so he'd probably have a different view on Thors' supporting cast. And the fact that the deaths were so unceremonious and just...there, really didn't help. Not to mention Sif probably would've been gutted if she'd been in it.
I think Loki kind of got his teeth pulled out as a character and got played much more for comedy, so not exactly similar in my opinion.
Fandral and Volstagg's archetypes are still pretty common in the modern day, but I guess if you didn't really look that deeply into their characters they probably wouldn't strike you (but I prefer a more Shakespearian Thor myself).
Thors' current supporting cast in the MCU is pretty weak in my opinion. It's, like, three people now and one of which isn't even supposed to be part of his franchise. Although I feel like the only MCU franchise to really maximize the supporting cast was Black Panther (maybe too much so) and I guess Ant-Man. Like in an ideal world we'd get BP level Thor movies.