I think it may be quite extreme as VC money doesn’t necessarily mean they will close at some point or malicious. I don’t have any good examples of a good VC-backed service though so ¯\_(ツ)_/¯
It may not be straightforward to figure out criteria to filter out companies like this. In addition to what others said about being more conservative when adding not well established services, maybe we can define some red flags which could point to possible issues with them? In Skiff’s case for example they were trying too hard to promote themselves using all possible channels like PG (even scams like PT), attacking other services via their blog posts and not being shy of spreading disinformation about them.
Another example is shady audit claims without actually posting reports which I honestly surprised didn’t raise any red flags in the past.