Because the reason decay exists in the first place on official servers is to make sure inactive people aren’t hogging land that active players could build on 
The official servers are for everybody and you do not have any “more” right to it than others, if you’re inactive and can’t play then official servers are simply not meant for you by design…
If you want to play in a lively world but your personal schedule doesn’t allow for you to log in frequently enough, then you can either join a private server without decay (or with a longer one) or make your own and advertise it till it becomes a “lively world”.
Serial refreshers are a big problem on official PvE servers, especially since most players overbuild and take up way more space than they reasonably need.
And if you look around, there are several other threads that try to find solutions for it (by suggesting various systems where people MUST play and not just log in to refresh the base)
Sooo all of the above is pretty much why a “counter-suggestion” enabling serial refreshers to thrive even more will probably not gain a lot of popularity around here.
I did have one suggestion though that “might” be more friendly to people who are actually active, but have varying schedules so they can’t log in all the time.