Can mean a couple of things, including, but not limited to:

1. An indie musician or group who dropped their indie style and started making pop or rap.
2. A YouTuber who dropped their unique content and started making videos about Fortnite that are only entertaining to toddlers.
3. A politician who dropped their unique point of view for another one which is more popular.

In any case, there is a certain group of people that is left alienated, confused, and angry. Thus, this phrase.
1. I used to like Panic At The Disco before they went mainstream.
2. I used to like Lazarbeam before he went mainstream.
3. I used to like Andrew Scheer before he went mainstream.
by AtlanticComputer August 30, 2020
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