Yes, it would be incorrect to describe a W boson as a 4th generation charged lepton. The W boson is not a lepton but rather a gauge boson associated with the weak force in the Standard Model of particle physics. It mediates the interactions between particles involved in weak interactions, such as the decay of elementary particles.
On the other hand, charged leptons are a class of elementary particles that include the electron, muon, and tau, along with their associated neutrinos. These leptons do not participate directly in the weak force as mediators like the W bosons. Instead, they interact with the W bosons as carriers of the weak force.
The concept of generations in particle physics refers to different families or generations of elementary particles. The Standard Model includes three generations of charged leptons, with the electron being the lightest and most stable, followed by the muon and the tau. Each generation includes a charged lepton and a corresponding neutrino.
Therefore, the W boson is not considered a charged lepton or a part of any lepton generation. It is a distinct particle that plays a crucial role in the weak interactions of particles.