This same solution will also let me fully remove birt from simrel as at the moment WTP depends on com.google.protobuf, but the only current contribution to simrel of that bundle is BIRT and that bundle is old with a signature. See https://bugs.eclipse.org/bugs/show_bug.cgi?id=568136
Please let me know if you have any concerns about this. Or even better a +1 if you think this is a good idea.
However, until Orbit also stops publishing jars with different signatures but same qualifier we may find it difficult to get rid of all the old/bad signatures in simrel as I don't think the tools today can enforce which p2 repo an identically versioned bundle comes from. I hope this can be improved with a combination of moving all Orbit to git and the great work being done to move Simrel to tycho.