I would like to tell my personal disagreement with Kraken:

on September 26, I made a BTC deposit to my Kraken account, but I made a mistake by sending funds to my USDT account. I asked for the help of technical support but they replied that it was impossible to recover the funds, as the process of recovering the private USDT keys was risky and burdensome.
So, despite my insistence, the funds were frozen in an unused BTC account.

Well at a distance I re-checked the BTC account corresponding to the USDT address I sent the funds by mistake, and I saw that they were taken!
Since only Kraken had the private keys of that account, it is obvious that someone has recovered the private keys (but it was not impossible?) And he has appropriated my funds without communicating anything to me!
I attach the account link, so that you can check out what happened.

https://blockchain.info/address/3GfhTD7LTNdPNj6niG6fKtwgjFYaXGtNzt

It also seems that the same fate is touched on many other erroneous transactions like mine: I'm not a big blockchain expert, but I leave the conclusions to you.

I have submitted a new complaint to the technical support, but I do not expect to have positive feedback, given their subtle behavior.
I think the community should be aware of this episode.

If Kraken has something to say, I hope to come forward:I know perfectly that other exchanges, in similar situations, have solved the customer's problem by returning the funds.
Apparently, Kraken's policy is to declare it "impossible," except to take those sums and make them their own.