[alserio]

I haven't coded c++ professionally since a couple of standards ago. However, I believe that something like c++ modules can be picked up quickly even by "middle of the talent pool" devs, because it's a useful feature for them. What might hinder modules adoption, beside availability of the compilers, is the rest of the tooling ecosystem and the particular idiosyncrasies that most c++ projects have.

[bombcar]

In every major project I've been involved in (and it's not terribly many, to be fair) things keeping us on previous versions were almost always libraries or other support software, rarely if ever was it the devs.

[Longhanks]

Really? For me, it has been almost exclusively management not wanting to invest the manpower necessary for the adoption.

If the technology stack allows it, I assume most passionate developers would develop rather with newer than older toolchains.

[bombcar]

These might be two sides of the same coin - usually the reason there is a huge manpower requirement is because of the libraries and supporting tools.

Most developers want to use the newest and greatest, but are held back.