I avoided Qt for a long time due to what I'd heard about moc being required. However recent versions support connecting lambdas to slots which is sufficient for my relatively simple application to avoid using moc to set up signals/slots.
Do you have a link that shows how to compile a Qt app without moc? I looked specifically for this and could only find this, which is unofficial and contains a bunch of ugly macros: https://woboq.com/blog/verdigris-qt-without-moc.html
Just don't use slots.
You should consider that c++ lambdas does not offer the same level of connection that signal/slot does (direct,queue,blocking,unique) ...
True, but a lot of that functionality can be gained using boost::signals2 and a simple cross-thread queue. (though some may question the wisdom of trading one dependency for another, I prefer my dependencies decoupled from each other). Still, as I said, lambdas are enough for my simple application.