This process of mere updating, despite the availability of resources for it, is complex to implement.
You can provide only the update files, but it would be necessary to develop a mechanism to automate the process of applying these updates, especially for non-technical users.
For example, I distribute my Android game as two separate files, and people often have extreme difficulty understanding how to copy a file to a folder. Imagine people managing small update files.
Furthermore, there are difficulties when modifying older files that are overwritten. This can create challenges for developers when renaming or reorganizing files in the game folder. It would be impossible to rename files if the process were entirely manual. (Rsync could be an alternative, but it's not native to Ren'Py.)
I can foresee a ton of questions about how to apply an update or, the person downloading the update from and trying to apply an older version and getting an error.
All of this process requires appropriate programming experience, and most of the games available may be created by individuals who are just starting their careers in the field.
I believe the best way to do this is to fully manage the updates just through the game like some programs do, steam, epic games and others, and we still have to think that, this requires internet access, and I notice that many players do not like to play, with active internet.
When we think about developers who might be willing to create this mechanism, it's important to acknowledge that many games here are being made available without the developer's authorization.
It's likely that the developer would create a system to prevent people without access to their Patreon from downloading the update.
The individual with Patreon access would be responsible for identifying the update files and making them available here.
It's possible that this person may not have the same level of dedication, and we would find ourselves back at the starting point.
Taking into account all these variables, I believe it's more beneficial to maintain the current system as it is and instead consider increasing our internet plan.