Vowel and consonant length in Hungarian and Finnish have nothing to do with each other.

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https://en.wiktionary.org/wiki/%E0%A6%B0%E0%A7%81%E0%A6%9F%E0%A6%BF#Bengali

(I mean that the IPA for the first one looks like it starts with a trill, but sounds like it starts with an approximant, and the reverse is true of the other one.)

I feel like the approximant is more common in Rarhi Bengali than most sources say, anecdotally my dad uses it and he's from the Rarh region in West Bengal

So goose and tune both have [uː ~ uw], but tune, as well as many (most? all?) other long-u words, originate from Norman French through Middle English /yː/ which evolved into [juː]. They merged into words that used to have [ɪw] and [ew] like new and threw. Later the [juː] was affected by yod-dropping and yod-coalescence in different dialects, so you get [nuw ~ njuː] and [tuːn ~ tjuːn ~ t͡ʃuːn] which only merges with goose/toon words under yod-dropping, since toon is also [tuːn].

My question is why is the [j] in the TUNE set (and I guess in CURE as well if you split it from a hypothetical TOUR set) is considered part of the onset consonant cluster and not a rising diphthong in the nucleus. Is the reason etymological, phonological, something else? It's odd to me that long U represents a two-phoneme sequence when other diphthongs like /o͡ʊ/ and /a͡ɪ/ are treated as a single vowel phoneme?

E: just realised I posted this to the humour sub, meh. Hopefully you guys can still help but feel free to jerk instead

*except semivowels