If anything it seems the opposite. The higher end models have more issues and the extra features on them don't always work smoothly. The MSI X670E Tomahawk has pretty good ratings while the higher end Carbon and Ace models have many reports of issues with PCIE dropping out and other things.Do you use all the features of the expensive boards, or could you have opted for ones with less?
I chose the ASRock X670E PRO BS because it was low cost, had the features I needed and I have a sound card.
I‘m just wondering, as I don’t suspect there’s any evidence that the most expensive ones are the most stable/durable?
I have had numerous Asus boards in the past and some Abit and DFI too, but my last few were all MSI. Once you get used to one brand's BIOS and windows apps, it's easier to just stick with them. The MSI X670E lineup uses Realtek network chips instead of Intel ones that reportedly have issues. All of the major brands have been guilty of auto-OC overvolting in the past, Asus is not alone there. I do think the Intel platforms are more robust than AMD ones, and that applies to all the motherboard brands. All the AMD platforms I've used felt cutting edge but had a bunch of little issues, while the Intel ones were rock solid, and the X670E follows that trend.