I’ve heard of Kotlin in the context of Android apps, but never actually used or learned it. I did one mobile app dev project with Java in Android Studio, but never had any formal classes on it either and just learned as I went (the result was shit, but we got a decent grade for being able to evaluate the difficulties and shortcomings and point out learnings).
That’s what I do too - if it’s a meeting I care about, I make the effort to suggest a different time. Otherwise, just decline. My calendar is visible and up to date, use the fucking scheduling assistant to tell you when I have time ffs.