A lot of crap here in this thread again.
Ok, so this question has been asked like 4879648657468 time in the past few months.
Expired web 2.0s or fresh web 2.0s for that matter will never be as strong as a standalone domain designed for PBN. The difference is not even close. Web 2.0s serve primarily for diversity. They will provide, especially expired ones, some boost, yes, but do not expect to rank anything half competitive with those, it simply won't happen.
When looking for expired web 2.0s, completely disregard idiotic DA/PA. With Tumblrs, look for the amount of d0follow backlinks and then TF. With any other web 2.0s, primarily look at the number of referring domains and then TF.
With expired domains it's a bit more complicated, they can be penalised or toxic and it requires a bit of experience to know which ones are good to use and which are not. There are a few guides online about this and you can also outsource it from people like me.
Also, building a PBN is XY times harder than just making a web 2.0. But XY times more rewarding.