A lot of depends from the project. Now gaming NFT projects attract a lot of attention and their airdrops are very popular. Just see the results of this airdrop
https://twitter.com/spacegrime/status/1396545308809601025 and you can see how popular gaming airdrops and how many users they have.
To understand how high will be liquidity of the coin it is necessary to check how many users have the ecosystem of the project. One of the best way to icrease the ecosystem and attract new users is airdrops.
Now many of the projects are actively use airdrops to attract attention to the coin. Airdrop help to attract attention but a lot of depends from the project how new and useful it is for people.