@amadeus by the way there are several issues regarding the licenses of the frameworks, critical ones at that.

LV2 is liberally licensed https://gitlab.com/lv2/lv2/-/blob/main/COPYING
It is not under GPL as the page states, please correct it.

Also VST3 SDK is not free for non-commercial. it is GPLv3+ alike JUCE where you can use it on GPL projects but proprietary software needs a license. (*)
Anyone can make a commercial + open-source VST3 plugin, no limitations there.

* VST3 has a GPL-incompatible clause