Craigslist is a perfect example of this. I've seen a few competitors pop up like letgo on mobile but it's hard to beat Craigslist's simplicity. The downside to following this approach is that your website can end up looking like Craigslist, at least that's what this site reminds me of.
It looks like CL is hiring a React and Mobile Developer, so it will be interesting to see if that leads anywhere new. Personally, I hope their site looks the same in another 20 years.
There are numerous Craigslist redesign projects on Behance that looks visually stunning down to the smallest details. But, I think there's something about mirroring the text-only aspect of newspaper classifieds that makes Craigslist feel familiar and appropriate.
Obviously that plain text style wouldn't work for Facebook, but probably equally so a highly visual/slick look wouldn't with as well for Craigslist.
It looks like CL is hiring a React and Mobile Developer, so it will be interesting to see if that leads anywhere new. Personally, I hope their site looks the same in another 20 years.