Maybe you don't remember, but I certainly recall the nation being legitimately worried about NK launching a ballistic missile at us before that summit was announced. Irrational fear, likely, but tangible nonetheless.
Again, this isn't about what he did at the summit. This is about the mere fact that Washington accepted Kim wasn't giving up his nukes. Unless you think you can talk him out of them, or that our sanctions are working, or that we would be better off militarily "restructuring" North Korea, then there is no choice but to meet with Kim and use diplomacy of some sort.
Given talking him out of them is futile, and that most people hate our willingness to apply military solutions to problems abroad, I fail to see how merely agreeing to a summit without stipulating denuclearization was or remains a bad decision.
Biden has already met with Putin and Xi. Sometimes you have to face the bully because punching their lights out would cause more harm than good.