The competition of the term you are trying to rank plays a huge difference in what works.
On many platforms, you CAN get expired 2.0s. On these same platforms, some are Do - Follow. If you scrap your own PBN domains, you can scrape your own 2.0 domains. They can have better metrics than many normal expired domains for less.
But these 2.0s are not as powerful as a single PBN link. The reasons are various, but in most cases, yes, a PBN site where all link juice is funneled via a single link is more powerful than your typical web 2.0. But you can get an expired 2.0 and funnel some lower quality contextual to pass more juice and authority.
For low / medium competition KWs, you can rank just as well in most cases with either a 2.0 or a PBN link.
But from medium to high comp KWs (Which people often confuse, search volume means nothing. You need to look at the top ten or twenty competing pages, see if they target the KW directly, how many links they have, age of the sub page on the domain and so on.) I typically, in my experience, have far better results with PBN links than 2.0s. Even amazing expired 2.0 domains on a Do - Follow platform which I beef up with profiles, other 2.0s of higher quality and metrics and high metric blog comments, and lower quality PBN posts do not move a high competition KW as well as a good PBN link.
For lower comp KWs, long tails with low comp, and some lower comp medium comp KWs can be ranked with well done 2.0s.
But try to rank for Payday loans and see how that goes. This is experience talking. This is why the 'big players' have a PBN and people suggest a PBN. Once you go after a higher comp KW, for your site or commonly for a client, you will see it is not worth it to manage 2.0s and they are not as effective.
I am currently working on several hundred KWs on various sites. One KW, one of my highest comp KWs, is a bit over medium comp. Top ten has 5 or so authority sites with exact match to the KW. Monthly search is over 30K. Page two and three are filled with sites with age, real PR up to three, high TF, good back links, and at least several dozen links pointing to their page which targets that KW. My site in on page four most days. I drop one of the aforementioned 2.0 which takes me more time than a PBN domain to build, and it does not move. I sprinkle in five, it moves up a space if I am lucky. Or, I drop a single well done PBN link and it moves.
The way I see it is like this, if I am going to spend as much if not more time building a 2.0 than a PBN site, why not build the PBN site? The cost difference is hosting plus the domain reg fee if you scrape them yourself. So $15 a year? It is more powerful and you have more control over this platform. Plus, PBNs, even when I use individual hosting accounts, are a LOT easier to track than a network of 2.0s.
For those lower comp KWs you can just build a few 2.0s on expired 2.0 names, prep them, build some lower quality PBN links to them and add content on a weekly or monthly basis like you would a money site. You can rank well this way for easier stuff. But depending on the KW, it changes what works and how well.