Yes, the risk of debasement is real.

Risk levels.

|Least Risk|   |   |   |   |       | Greatest Risk|
|---------------|---|--|--|--|------|---------------------|
|BTC           | LN | Ark/Mercury | Liquid | Fedimints | eCash | Bitcoin Bank/CEX |


freetx

The mint is trusted in three ways:
it’s trusted not to lose/spend/steal all the funds backing the coins it issues;

it’s trusted to correctly use its private key when doing blind signatures; and

it’s trusted to accept coins it issues either to replace them for new coins when ecash is being transferred to a new owner, or to redeem it for the bitcoin it’s backed by.

ecash

Ecash and lightning via ZKCP

Rsync25

It says right here 
> The mint is trusted in three ways:
it’s trusted not to lose/spend/steal all the funds backing the coins it issues;

> it’s trusted to correctly use its private key when doing blind signatures; and

> it’s trusted to accept coins it issues either to replace them for new coins when ecash is being transferred to a new owner, or to redeem it for the bitcoin it’s backed by.

So, it's based on trust? 

Least Risk						Greatest Risk
BTC	LN	Ark/Mercury	Liquid	Fedimints	eCash	Bitcoin Bank/CEX