Physicists see it as their most magnificent equation. Agreed, the Lagrangian is beautiful.
And yet, is it ?
Look into it, and it is missing gravity.
[It is also missing the hallucinated dark matter XD, why, could Cosmologists not convince Particle Physicists about how cool their hallucinations about 95% of the universe are ?]
It uses the gauge group SU(2)xSU(3)xU(1) to account for the symmetries of particles and their degrees of freedom.
And yet, it fails to answer so many questions, theories that use it refuse to answer why they treat particles as points, and point excitations in case of QFT. Why do all these particles, with, as per you, different origins, different force carriers, and even different symmetries, come together to form a universe where everything works like clockwork ? Why does the Higgs Field give mass to all particles, without caring for their independent origins ? Why do these different classes of particles all agree on having interactions as per the same force ? Why do forces need carriers ? Why do you need invisible photons to carry electromagnetism ? And even if they do, why do they allow interactions between these independent classes of particles as per the same equations ? Why do you need to violate mathematics and introduce renormalization if your model is so perfect ?
Further, the SM is more of a top down approach, which relies on mixing in every new particle they find with its independent origin into the same Lagrangian. Why are you doing this ? Why not do it the rigorous way ?
Design a topology with invariants and structure rich enough that particles are emergent as topological entities with unique degrees of freedom, with forces as topological interactions between particles without hallucinating force carriers ?