@freemo >the viral nature
No copyleft license acts as a virus, as copyright cannot infect merely aggregated software - it's a spider plant nature, if you explicitly take a piece, the freedom grows.

>the lock-in that resulted
Please don't twist terms to suit your argument.

License incompatibility is completely different to lock-in

>for example it prevents switching or in some cases even using other copy-left licenses
If you want to change the license, you need permission from all copyright holders - this is true for all licenses.

>There have been countless open-source projects that had to be abandoned and restarted from scratch
I've only really heard of cases where people developing a project wanted to make things proprietary and a freedom defending license said no - which is a feature and not a bug.

I've heard of a few cases where projects determined that there was an incompatibility with other projects due to a poor licensing choice, but in the end, the goal of compatibility was reached by asking copyright holders to relicense and re-writing the few parts by non-cooperative or unreachable holders, but certainly not to the level of a full re-write.


People and those writing licenses have had 17+ years to be compatible with the GPLv3, so compatibility problems now were arguably foreseeable and intentionally made (too bad some people are still intentionally setting themselves up to be incompatible with the GPLv4 (if it's ever required), by licensing GPLv3-only or LGPLv3-only).