Depending on your use-case there are a lot of options to consider before investing in a professional solution like Ableton Live.

- LMMS[1]: The go-to cross-platform FOSS DAW solution, with VST support and a healthy community.

- Ardour[2]: Much like LLMS, it's a classic Open Source project that runs cross-platform and is quite fully-featured.

- VCVRack[3]: A brilliant FOSS EuroRack Simulator. It has a built-in package manager with an enormous selection of officially supported and community submitted plugins, complete with VST and Linux support.

- Waveform Free[4]: By Tracktion, Waveform is a robust DAW with VST sandboxing and great built-in FX.

- Audio Tool[5]: A great web-based DAW, featuring online collaboration. Last I checked, there was no VST support.

- Bandlab[6]: Another web-based DAW by the folks behind Cakewalk. While it lacks VST support, it offers online collaboration and straight-forward defaults.

If you like scripting, Reaper[7] offers a personal license for $60 and supports Lua, Python, EEL2/JSFX, and it's own ReaScript[8]. Reaper offers a highly customizable, robust solution for power-users. While the above projects are some of the more complete projects, there are many more scattered around Github. If you're interested in the more niche/experimental ones, let me know and I'll reply with my more comprehensive list.

That being said, I've been an Ableton Live user for over a decade and I recommend it for anyone who wants to invest into a more serious music project. These days, I tend to reach for Studio One[9] by Presonus for more involved projects. While it lacks the focus on live performance, it is more feature-complete DAW than Ableton. Studio One doesn't have the same friction-less workflow that Ableton is famous for, but it's an absolute powerhouse when mastered. It's very well funded and one of the youngest, so Presonus had the opportunity to adopt the best features of more dated solutions like Cubase, Logic, Pro-Tools, and Ableton, while stripping away a lot of the bloat.

[1] https://lmms.io/ [2] https://ardour.org/ [3] https://vcvrack.com/ [4] https://www.tracktion.com/products/waveform-free [5] https://www.audiotool.com [6] https://www.bandlab.com/ [7] https://www.reaper.fm [8] https://www.reaper.fm/sdk/reascript/reascript.php [9] https://www.presonus.com/products/studio-one/