Servers have a unique benefit that all other submission types do not have and that is an active engaged following. Often that following is used in small part for financial gain as servers cost to run and so many servers that cannot bring in enough paying players end up shutting down. More often than not servers which dont shut down due to lack of funds make an excess over their cost and many servers reinvest at least a part of that into the server but some do take the extra for themselves.

Xp is given largely for contributions to the site in the form of content, but mostly people post things here because they want to share their unique creations, the xp is just a bonus. Just like with texture packs, mods and data packs that require constant attention and updates to stay relevant with new game versions, servers require that attention to stay relevant with the player base. These updates are optional and the reward being that you can update the submission bringing in new people to look at and interact with the post. All submission types with the exception of servers may only make update logs if they are providing new major changes to their post. Server posts on the other hand get free bumps once per 24 hours without having to provide any new content to viewers.

Aside from that a large chunk of server owners large and small often try new underhanded things to get one over on other servers and something like this would only encourage more of that so I personally do not feel this would be a good addition.