Maybe if you are suggesting to retire a whole word out of the language you could at least provide a (valid) reason to do so? It's not really obvious and a bit surprising, honestly.

The blog author speaks around 15 languages competently and he reads in about 15 more. Here's a 2 hr long interview with him where he touches on this topic: https://azeletmegminden.hu/040-sajo-tamas-podcast/ (in hungarian)

"Polyglot" refers specifically to language though. I've always taken it as someone being fluent in > 3 languages, following biligual and trilingual.

Based on your proposed alternatives, you're likely thinking "polymath".