I've seen a number of posts like this usually wanting a specific device that is good for kids that has the appeal of old computers. The answer is that any laptop loaded with creativity app works great if you have an attitude shift that it is a creative device rather than a consumption device. Choose your apps and get used to building things with it. Avoid social media, youtube, netflix, and the fun will come back.
The shortest jam I've done so far was a week (PyWeek) and although my team won we barely finished. 48/72 hours seems tough but I really want to try it.
AI music will be cool for 10 minutes and then you realize one of the reasons you listen to music is about shared human experience. If it’s just a generated blip that everyone is generating and resharing it’ll eventually have the same appeal as blogspam. AI music will cause people to go back to seeking out performed music played on instruments or in a live setting. You'll have music sites that only allow music that has videos of humans playing/creating it. Every AI action will have an equal but opposite human reaction.
For me depression comes when I have low amounts of energy, which I've since realized is affected by my nutrition. If I eat too many carbs or sugar, I get extremely fatigued and then get depressed. It also causes me to daydream and have a hard time concentrating. Maybe keep a close eye on what you're eating/drinking and see if it's related.
I haven't worked on it in a while, but you might like textbeat (https://github.com/flipcoder/textbeat). It's a midi tracker and REPL that lets you type in music theory-like terminology and plays it. It's nowhere near a modern DAW but it's cool for tinkering and learning.
I own a LinnStrument and it's fantastic. I created a custom note layout for it to make it easier to play: https://github.com/flipcoder/linnstrument-wholetone. The firmware is also open source. It feels like the Linux of instruments.