Although it claims that it has been tested to up to 1.13, I'm seeing reviews that indicate that it works on 1.14 and 1.15(based on the date the reviews were posted), and since it affects a certain gamerule part of Curse of Vanishing it's likely not going to matter much when it comes to versions.
Or did you mean out of date as in the API version is lower than minehut's minimum compatible API version?