As of November 4, 2020, the work has been done regarding the merge of the Sonic Mania Plus leaderboard back into this old one after deliberation done with the other Sonic mods regarding the future of this game. We saw it fit to now merge the games back into one board due to factors relating to the devs having been moved on their own paths beyond working on this game any further. We took into consideration the possibility of the game having more patches/updates that would have further changed the game on a gameplay level that would have warranted further separation, this is why the split of boards happened in the first place back in 2018 when Plus launched. This is no longer the case where this is a concern so this idea became obsolete which lead to this merge taking place.
To quickly address the reasoning regarding why the old board was chosen over the new one, the old leaderboard was ultimately the larger board of the two with more runs recorded despite it only being used for barely under a year unlike the new board's 2+ years at this point. This reason alone along with historical purposes is why the old leaderboard narrowly won over the new leaderboard.
From an (edited) announcement I made in the Mania channel on the Sonic Speedrunning Discord server:
"[...] Three key changes have been done to the leaderboard to accommodate for this are as follows:
- Added all categories (and new/transferred rules) from the Plus leaderboard for full game runs and ILs. This includes guides and resources too.
- Due to runner request, the Emeralds variable for non-Sonic characters has now been converted into two separate subcategory tabs: 'No Emeralds' and 'All Emeralds'. All No Emerald runners can now have fun optimizing the game without having to deal with Emerald shenanigans.
- All Unpatched/Patched ILs have been separated through their two separate version tabs respectively across all levels instead of specific ones (where certain exploits/skips were only doable in Unpatched, therefore making them impossible to beat on Patched). This makes the layout of the IL board more clean and consistent to navigate.
- Everything else minor from the Plus leaderboard etc.
I also have another special announcement to make, we are now offering appointed verifier positions for new fresh people to help out on the board for any runs that need to be verified! You can find the application for this through the link here to fill out: https://forms.gle/GMcHYGqKcDrzkTz98
There will be a 3 week waiting period (starting from November 2, 2020) to ensure the process of picking out the best candidates is done carefully (2 will be chosen, possibly 3 if the number of applications submitted is high) giving plenty of time for people interested to see and submit."
If any runs were missed or messed up during this merging process then please let me or another Mania mod know through a DM so it can be corrected (or just resubmit, that works too). It's also worth noting all Plus runs that no longer have a functional VOD as of the time when the merge started were noted as 'Mod note: Deleted VOD' or something similar along those lines, just in case if that might sound misleading otherwise to anyone. Lastly, all forums posts from the Plus leaderboard have been cataloged so all the history and data from that board are still intact in the hands of the Mania mods. Thank you for reading.