They are not trying to prevent you to buy or sell monero, they are trying to just make sure you do not do something illegal that they allow. Monero might be fine, or might be illegal, you may do something nice with it and buy your mom a flower, or you may buy drugs and sell it to kids, we have no idea. So they ban it, to make sure they save their own interest, which is why I believe we are going to see this growing to be something much better, we can't have anything marginally better at times.
Then why they still allow EUR, USD, and other FIAT currencies when they are still the most used ones for all the bad things ?
FIAT money is physically tainted with drugs, blood and feces. It's so dirty I have to wash my hands every time I touch any of it.
Money, no matter in what form (even CBDC) will always be used by criminals, fungible money like Monero is making sure our hands don't get dirty in the process because someone else before us used it for crime.
The world is not black and white, the "illegal" sticker can be put on anything by the government - even on supporting homeless people.
I think there are some chain analytics that could be done with your LTC. If something comes in and could be related to the swap, it can be connected to you in some way, especially if it is from something illegal. I don’t think it’s a problem to swap and then deposit it in a different currency; it’s just that they don’t want XMR to be their platform. It might be regulations, but it’s still up to them.
Kraken has publicly expressed many times that they love Monero, so it's not that they don't want it - they were forced by the EU regulations written by people who want CBDC to be the only currency while allowing some transparent blockchains that they can surveil.
As for LTC - it's only a proxy, once you go to Monero chain, you're free.
If they choose to suspend people who swap, that's their choice. They will lose a lot of business and people will go to DeX, Serai will soon be released with it's liquidity-pool, it will be game over for CeX.
No biggie.