Just listing some possibilities, different projects have different needs. Sure, for most of the cases the dynamically linked open source version works just fine.
Qt for Device Creation needs a license, that one is not available as LGPL. Of course you can use the open source Qt yourself for that, but then you'll be facing a lot of platform work to get Qt running on your device before even starting with the stuff that you actually want to build.
Qt for Device Creation needs a license, that one is not available as LGPL. Of course you can use the open source Qt yourself for that, but then you'll be facing a lot of platform work to get Qt running on your device before even starting with the stuff that you actually want to build.