Python and NodeJS both beat Lua because they were scripting languages involved with web servers and web clients, and the massive influence of the web on the job market meant that everybody was going to want to learn Python (and Javascript) and then try to apply it blindly to everything.
It doesn't matter if either language might not be competitive with Lua or any other language in terms of design / features.
I would agree with this point in respect to Python, but not Node.
I think Node was in large successful because web developers already have to use JavaScript so the promise of unifying on one language and set of libraries is appealing to many.
OpenResty and Lapis are quite capable in the web space, but they haven’t seen widespread adoption.
It doesn't matter if either language might not be competitive with Lua or any other language in terms of design / features.