I read that a potential reason why Argon2 might not be used is because it’s not “hardware accelerated”. I decided to play around with several different implementations of Argon2, like Keepass, npm node package, and some arbitrary javascript implementation to run in a web browser. They were all within a factor of each other. Some a security standpoint, that’s a “1 bit” difference.
Also less than a factor difference between Samsung S7, Intel i5, Samsung S20.
Other than development time, I see no reason to not do this. May want to warn the user about setting memory too high. May also want to have some way to test how long it will take for a calculation. A simple page with the config options and a timer would suffice.