ACM Computing Surveys
https://dblp.org/db/journals/csur/index.html
https://dblp.org/db/journals/csur/csur56.html
A journal full of survey articles of a large variety of computer science fields. via a pair of toots:
I wish we as a field could develop a taste for SoK (Systemization of Knowledge) papers. especially with how volatile notation and terminology is, that chasing through a line of old papers can get time consuming real quick.
In case you don't already follow it, ACM's CSUR journal is all surveys and SoKs and they're often quite good: dblp.org/db/journals/csur/inde is a reasonably-ok way to browse the volumes. Here's a representative example from PL: dl.acm.org/doi/10.1145/1922649
(Unfortunately CSUR mixes all fields of CS together so you often have to wade through a lot of irrelevant stuff, I wish someone built a better thematic index!)
I still imagine a site that is a wiki with strong editors that has surveys available for a wide variety of fields, but this is a nice something for there to be at least.