... so what ? other companies can also write Qt libraries under GPL and commercial licenses if they wish to - why shouldn't TQTC be able to do the same ? It does not make the rest of Qt any less LGPL.

For reference, on arch linux, there is a grand total of 3 packages with a hard dependency on qt charts, one of those being a python binding to it. versus the whole of KDE plus a ton of other things that have no problem depending on "just" the LGPL parts of Qt.