The issue isn't really that complex. In regard to Twitter there's an ADHD-riddled megalomaniac running the company that doesn't understand his product. He's trying to treat a people problem an engineering problem and he's out of his depth. Twitter doesn't make anything and he makes things.
In regard to the company he bought, it was definitely bloated with too many people for what it does and it is quite representative of the software development and engineering job market in the US. Companies have been hiring and hoarding tech employees since covid started in a bubble fueled by what was felt as a need to adapt to a changing world. The tech job bubble is bursting ad a result of global economic factors and Twitter is the poster child of it.
Now that we don't talk about covid any more, and now that free government money has dried up for people who (because of paid influencers who get money from corporations to make propaganda videos) thought that the free money meant they would get to choose how and when and whether to work on their own terms forever like their favorite tiktokers, we are facing global crises defined by rampant inflation (from paying people trillions to sit at home and do nothing) and commodity price hikes from reduced production capacity in key sectors like energy due to war and lack of demand. People went from having the government paying their bills to having the money they have being worth 10-15% less in a year. So people stop buying, companies stop advertising, companies don't sell as much, people get fired.
Very little complexity in what happened at Twitter or any of these companies.