Yes and no. Twitter was started before so much of the common “web scale” Open Source projects existed. Cassandra, Kafka, Spark, Kubernetes, etc didn’t exist yet.

So versions of the aforementioned and then some were completely done from scratch at twitter, who has continued to maintain those projects despite them not being the premier open source offering in each of those categories. They also never achieved the scale of some of the largest tech companies where it makes economic sense to have say, a custom database or queue system.

Finally, Twitter has been using GCP for some of their new projects in the last few years, but they still had old legacy systems and teams to maintain that software, so they couldn’t fully reap the rewards of the cloud.

So, if you rebuilt twitter today you could likely do it for a fraction of the engineers they had at peak, by leveraging either cloud or popular existing OSS solutions. But that’s from scratch, not porting millions of lines of legacy code.

What Musk should have done was migrate various systems, then wind down teams. That probably would have worked, but been expensive in the short term.

So I think they cut too much, and I also think they honestly thought more engineers would be up for “hardcore twitter”, instead of quitting.

Musk forgot that all his very loyal Tesla employees may have also factored in their 10x RSU appreciation. It’s a lot easier to put up with insane working hours when your next years stock grant is 500k or million or something. Doesn’t apply at twitter.

Tl;DR: not a Musk hater at all, but he fucked up at Twitter.