Your statement sounds like GPL is giving a "freedom", so like you could use GPL code in an MIT licensed project (sorry if I misinterpreted your statement); this is not true, see https://www.tawesoft.co.uk/kb/article/mit-license-faq "Can I use GPL-licensed code in my MIT-licensed project? No. The project as a whole must conform to the terms of the GPL license and must be distributed under the terms of that license. Therefore such a project as a whole must be distributed as GPL, but can still contain MIT-licensed software."

So it is more like MIT licensed projects give you the freedom to use in a GPL project.

Free PyQT does not have the linking exception (which would be lgpl); only the commercial version has.

https://riverbankcomputing.com/commercial/license-faq