Turbo channels is not the problem with muun. The main problem with muun is that it is an on chain wallet always paying on chain fees, and using swap services to send ln transactions. This makes the fees large and unpredictable.

It also means that every ln payment is controlled by them. Turbo channels (in actual ln wallets) are just new channels that don’t have a confirmation on chain yet. So they only have a ten minute risk. After that everything is back to normal. I can take that risk to get a quick incoming transaction sometimes when I don’t have channel capacity.