TBMK, it is not. It's a non-AEOI/CRS country so some institution might take it as suspicious but I think it will be rare; PY it's not so popular.
Exactly, it is so quite often. Especially European EMIs and neobanks tend to have not a “prohibited countries list” (as any brick-and-mortar bank has, too) but a “permitted countries list”, very often containing EEA or EU or even Eurozone countries only... (the last one was the case︀ of N26 for a long time, no clue how it is currently; Bunq had similar︁ restriction).
YMMV; but AFAIK︂ it is not so easy. It can vary also from one bank to another one︃ but some ties to Poland are usually demanded.
I guess that LatAm itself is not︅ so a big problem. (US passport is remarkably worse, BTW.) But see above.
True, the Dukascopy limitation︈ can be the barrier if you do not have the limit sufficiently high; raising the︉ limit is not easy-breezy. But I guess that if you do not accumulate the cash︊ there, 10k should not be a problem (more precisely – 10k used to be an︋ entry limit; but I admit that this info concerned Europeans).