Minehut will update once Paper Spigot and most major plugins have updated to support the new 1.16 update. In order to connect to a playerserver via 1.16, the playerserver must have ViaVersion installed. This doesn't mean that 1.16 features are enabled on that playerserver. 1.16 features (blocks, mobs, terrain, etc.) are not enabled nor accessible at this time on Minehut. They have predicted roughly a week or two until Minehut updates.
No worlds will be deleted unless you delete them, no files will corrupt, and any new generated chunks will be in 1.16 style after Minehut updates.