I can't argue with that as you are entirely right. I have seen the software industry evolve big time over the past decade and I have seen Linux desktop changing from the bugged OS with barely any good software to a quite stable OS with much good software. I mean, we are entering an era where almost all software is becoming available for all platforms. It is not even justified anymore to publish to one OS because if you don't someone else will. That is the issue with software from Adobe too. There are many great alternatives and people are done waiting for a port to Linux or Mac. They'd pick other software that suits their needs. And I am very happy that I can use the same tools on my Linux machine as on my Windows now (except for Paint.NET) I could not do that last decade. And none of them are closed-source with an exception to Paint.NET that is.
Anyways, what I am trying to say is that you should pick the OS you wish to work on and than look for tools that suits your needs. You won't find the ones matching perfectly but still good ones. Open-source or closed-source makes no difference as it does not define quality anymore. There was a time when open-source meant buggy and unprofessional and closed-source meant quality software but that has changed drastically.
As for backups, I don't bother making them anymore on my Windows. From time to time I copy my documents to an external hdd but other than that the files are saved in OneDrive. Everything I work on is stored as git repo on GitHub so should my system crash, I would not lose anything at all.