I honestly have no idea why modern tech companies are so obsessed with this strange abstract minimalism that they've made so prevalent now.

Like why? It's just confusing to look at without context, shouldn't a logo tell you exactly what an app does just by looking at it? The old Gmail logo was good because it was a Mail Envelope with an M on it, for mail. The same goes for the Old Google Docs logo because it's a piece of paper with lines representing text on it: in essence a document, the new one just looks like some weird rectangle with a funny corner. Without context none of these logos work.

Reason for this: designers need to show that thery are still worth retaining and getting company's money, hence interface and icon "improvements" to increase "brand cohesivness" and "recognition factor", or whatever other thing they try to sell it as to their superiors.