Cross platform Open source notes apps?

I know this has been discussed a lot but so far there is no TRUE cross platform ones that work and syncs for free.

The closest is Joplin but that’s laggy and bloated.

Anyone knows of an app that

• Syncs
• Works on iOS Windows and Linux
• Free or affordable

Some apps I tried

• Bear app - my main so far but my macbook is aging so I am planning on getting a linux notebook and I have a windows desktop at home. I managed to stay with this the longest but only because I have an iphone, ipad and mac. But now, I want to try windows or linux as well.

• Notion- laggy. Bonus: free with education account, (I have one and it works but I don’t like its interface and database nature. It’s not as simple to just type and go.

• OneNote- laggy. At least for me. And definitely not open sourced.

• Standard Notes- good features but very expensive for what it offers. Especially if you want to use sync.

• Obsidian- not technically Open source but very popular. The sync is expensive though and does not even give you storage. It utilizes the space already on your device. Feels like a rip off.

• Evernote- I like its price proposition better than Obsidian but its bloated. And I don’t like its ethics.

Anyone else has ideas? :)