The thing is, at least for weed companies, that they technically are not legal on federal level where banks are regulated. The Obama, Trxmp and Biden admins simply have chosen for now to ignore the issue on executive level since Congress is completely and utterly dysfunctional, which is something the next admin/President can easily turn over and prosecute everyone involved, even for actions years past.

For porn (as well as, where legal, sex work and gambling), the problem is the immense amount of fraud associated with it. Horny people caught by their s/o's or company expense teams stumbling on CC bills or plain old "post nut clarity" has led to many fraudulent "card has been stolen" chargebacks, as did actual fraud by people using stolen CCs to sign up for porn sites and resell these accounts on the Internet, and additionally to that there are lots of legitimate chargebacks (dark patterns in account signup aka pre-checked "recurring" options, low quality content). And add to that the various issues regarding legality of services rendered (which may be different depending on where the seller and/or the buyer are located and where the service takes place).

And if that wasn't enough, the US likes to enforce their laws on companies based in the US also abroad... which means even here in Europe where sex work, porn and (in sometimes utterly incomprehensible ways) gambling are legal in most our states, we still have the problem that the US companies export their morality codes onto us Europeans (see also: facebook's nipplegate).

The result is legitimate businesses and mixed-content businesses (reddit, onlyfans) being struck by obscene merchant fees or being denied service altogether since it's frankly infeasible for non-local services, especially in physical sex work, to be in compliance with the myriad of rules ranging from global international agreements against drug usage and human trafficking over federal and state law to county/town ordinances.

I agree that these businesses deserve access to banking (alone to reduce the incentive to rob them of their physical cash!), but seriously the solution to that is a reform of banking, sex work and gambling legislation - not cryptocoins.