Firstly, IANAL/IANYL. That said, there once was a licence very like this, the original, aka four-clause, BSD licence. It contained the requirement that
All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by the University of
California, Berkeley and its contributors.
which some people referred to as "the obnoxious BSD advertising clause". The FSF's position about that clause and freedom is that
The flaw is not fatal; that is, it does not render the software nonfree. But it does cause practical problems, including incompatibility with the GNU GPL.
Your requirement is somewhat stronger: you don't merely intend to control the content of the end user's adverts, you mandate that they advertise.
It seems to me that software under such a licence would almost certainly not be able to be combined with GPL'ed code, and might well be regarded as non-free by honourable people like the Debian Project.