I wrote an extensive article about this: https://www.velvetshark.com/why-do-brands-change-their-logos...

Since its publication it even got featured in a Spanish textbook, and I get tons of traffic to it all the time. The topic seems very much valid for the last few years, with no sign of change.

The main reason seems to be to look good (or even readable) on mobile, but it seems that it's more of a bandwagon than a proven good strategy.