MSI's B450 tomahawk, mortar, pro carbon and bazooka plus have the best VRM on the B450 line and are capable of handling 16 core CPUs so not sure what Msi boards you were looking at but any research should have led you to one of these boards.
https://www.reddit.com/r/Amd/comments/c7qj5e/am4_vcore_vrm_ratings_to_help_you_decide_on_a/
Thanks for some balance - please note I am NOT anti-MSI - I was mostly just trying to urge ESAT to stop making sweeping statements about MSI always being reliable or "the best": they have some very good products, but they definitely have had their bad days and continue to do so (some X570's). Asus/Gigabyte also frequently have very good* products, but also some truly awful ones (e.g. early revisions of the Gigabyte B450 Aorus Pro!).
Currently I'm researching the "cheaper" X-570 boards: Here are some from the $200 range where MSI X570 was beaten by Gigabyte, Asrock and ASUS:
https://youtu.be/_7PkZwY9PWM?t=637 and only two boards completely failed the VRM thermal tests (both MSI's).
Note that MSI are one of the best for the $400+ X570 range though... but probably a bit expensive for me and there are more appropriate options out there as I'm unlikely to go beyond a 5900X CPU any time soon! The problem is that each design + revision varies so much, so it's not even possible to make sweeping recommendations about all variants of a particular brand + chipset (although shop very carefully with MSI+B350!).
@Joxeon - your Reddit thread links to videos in that same series I've just been watching on X570's: Steve's not kidding when he says "one board sucks!!" (MSI Gaming Edge WiFi).... note that yet again MSI pretty much "bookended" these tests (top and bottom), with the $700 "Godlike" as one of the best - *only beaten by a cheaper Gigabyte
https://youtu.be/xbyWKufthS4?t=622 again MSI at the bottom (MSI X570-A Pro)
I wouldn't even go so far as to agree with the Reddit poster "still don't really know much about the MSI X570 Gaming Pro Carbon. But if it performs similarly to its other MSI brethren then it might be something to be avoided." - MSI have some really, really good X570's... just quite a few bad ones too.
If I stumble across the MSI B450 tests that made me warn people against the "any MSI is okay" recommendation, I'll add them here.
In terms of the MSI B450's - I know they weren't all bad though - far from it! From reputation, I know that at very least the final versions of the MSI B450 Tomahawk Max were really great.
In terms of current builds and personal experience, the relatively budget MSI MAG B550M Mortar has proven to be a solid performer and very reliable: it is regularly on my entry level and mid-level builds and I've never had any problems, so it's fine on R5 3600 to R7 5800X builds at least and it appears to do well in Hardware Unboxed "torture testing" too... where they run extended multi-core load with mid-level and low-airflow cases.
The tests aren't necessarily reflective of how I'd build and setup any system, but it gives an idea of what it might be like when there's a year or two of dust in the system and the filters are clogged. It's nice to know that if one of those friends I've helped build a system for, decides to re-encode their DVD catalogue next year, it's not going to start a fire and burn their house down...