So many people seemed to treat the entire ten seasons as some sort of extended tease, a long frustrating prologue to the "real" story, which somehow only begins when Clark puts on blue long johns.
It's not a value judgment. There's nothing wrong with the fact that
Smallville was intended as a prequel, a take on the Superboy story minus the costume, or rather on the Richard Donner/John Byrne-style story of young Clark's coming of age before adopting a costume. I mean, come on, it was called
Smallville and featured Ma and Pa Kent, Lana Lang, and Pete Ross. That's effectively a Superboy series, a story about the part of Clark Kent's life before the standard Super
man part of the narrative in Metropolis with Lois and Jimmy and Perry. It is not in any way a criticism or indictment to acknowledge that well-established dichotomy between the Smallville stage of Clark's life and the Superman/Metropolis stage, a distinction that's existed in the comics since the late 1940s (with or without a Superboy costume/identity being part of the Smallville stage).
However, the fact remains that
Smallville was never expected to run for more than 5 or so seasons, so in its later seasons it outgrew its original brief and had to find other ways to continue the narrative. So it brought in more and more facets of the adult Superman/Metropolis story, and in its last three seasons it became functionally identical to a standard Superman story set at the
Planet in Metropolis,
except for the absence of flights and tights. Which made that continued avoidance feel arbitrary and artificial, a trope that had outlived its usefulness by that point. That is not a criticism of the entire show, merely that one superficial aspect that it oddly refused to change even after it allowed everything else about the premise to evolve and mature.