Sure and odds are C++98 is compatible with C++17. The problem is the reverse, I try to write the most modern C++ I can, but I'm limited to my compiler (in embedded systems we rarely get updated compilers) which sometimes means I have to write the c++17 library things I need in older styles, and of course I can't touch anything that needs a non-library update.

I haven’t done an upgrade from 11 to 17, but I did do a few 11 to 14 and there were a lot of issues with the boost versions we used. Those upgrades killed any interest I had in ever using C++ again.