I see this a lot in my lab (days/weeks to run computations and analysis that could take minutes/hours), and I used to offer to help the postdocs/phd students port their code from matlab to C/C++, but I've mostly given up on offering unless they ask for help, or if it seems like fun. I also think it's because they mostly think they won't work on these things again (which is kind of weird to think about since they spent most of their life working to get to this point, but that's another conversation).

Aside, I think armadillo is pretty great, especially going back and forth with other matrix libraries, also nice wrapper around OpenBLAS which made not running something on a cluster more bearable.