Are they actual project running some business in the wild? I only played with coq in university, while I saw F# being employed in insurance companies. I only heard about lean through HN posts.
I don't know about running per se but practical applications (as in done for product/service) exist. A notable practitioner for Isabelle and Lean is AWS[0]. There is also TLA+ for a more practical tool.
The most widely used variant of these proof assistants are probably formally verified compilers, like compcert, which are used in some highly regulated industries like aviation.
The most widely used variant of these proof assistants are probably formally verified compilers, like compcert, which are used in some highly regulated industries like aviation.
[0]: https://isabelle.systems/zulip-archive/stream/247541-Mirror.... and https://lean-lang.org/ (Cedar)