Back in November of 2015, Google expanded its Local Guides program with a points and level system that introduced new rewards for each tier. At 200 points, you would reach the coveted Level 4 and receive 1TB of free Google Drive storage for 2 years. Now Google is backing away from that promise and lowering the amount of free storage to 100GB only.
It might be that Google Maps' recent updates that incentivize you with notifications to post photos, reviews, and answer questions about places you're visiting has had a positive effect and Google is seeing more and more people reach Level 4. This is why, in order to provide everyone with free storage, it's lowering the amount to 100GB instead of 1TB. At least that's the reason given to Local Guides in a new email that's going out to them:
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