Without liquidity it is impossible to survive.
There are a lot of DeFi projects and there is a big competition among them.
In such a competition win only the best projects with biggest liquidity and big choice of different tools.
Very often accounts of users on centralize exchanges are blocked for different reasons but it is imposible to block the account on DeFi exchange.
That is why DEX so popular now and in demand.
For DEX security is very important. Users must be sure that their fund are kept in a safe place.
Also for DEX it is necessary to gave a good liquidity and offer the best conditions for liquidity providers.