"LGPL requires that the end user be able to replace the LGPL-licensed shared library..."
So far I am with you
"...or it turns into GPL"
Can you quote the passage of the LGPL that says that?
"The problem is, end users have no access to replace shared libraries in embedded or even mobile devices"
If one takes an embedded device, say a Raspberry Pi, and puts a Qt based application on it, how exactly is the end user of said device prohibited from changing any LGPL library?
"Of course this only matters to closed source software."
How so? I was under the impression that the licence clauses of the LGPL for a library applied totally independent of what licence the application code is using.
Can you quote the passage of the LGPL that says that FOSS software is relieved from the obligation that user are allowed to change the library?