Personally, I don't see much future in those privacy coins. I think the idea is amazing, but in real world it is going to be something like a deep web money.
But even if you're using crypto for things that aren't illegal and/or aren't found on the dark web, what's wrong with complete privacy (or as much privacy as these privacy coins can give you)?
I also think the concept is amazing, and it's one of the things that's perplexed me in the last couple of years, i.e., why coins like Monero, PIVX, Dash, and whatever else is considered a privacy coin haven't caught on with investors--even most altcoin owners seem to not be too enthusiastic about them.
I just took a look at Kraken's website, and I couldn't find any info as to where they're incorporated. Is it Australia? For some reason I thought they were based out of the US. But as far as to why they're dropping the coins mentioned in the OP, I'd imagine it's because of the government and not a request from banks. It's the governments that have a hard-on about money laundering and dark web use, not the banks IMO. In any case, this is kind of a sucky precedent that I hope doesn't spread.
