https://constitution.congress.gov/resources/unconstitutional...
But that’s just the federal branch. Your list includes states and local municipalities - which makes the real number much, much lower. Much closer, arguably, to 0.1% or less of all legislation.
The idea that the court would not give proper scrutiny to a legislative act -- one which may violate the first amendment, fifth amendment, and may amount to an illegal bill of attainder -- just because it had support from the senate, well, that's just preposterous.
You're missing the giant flip side of that coin; that local, state, and Federal courts can all determine laws conflict with other laws or the Constitution, and do so regularly.
(For example: This never needed to go to SCOTUS. https://www.aclum.org/en/press-releases/states-highest-court...)
Things largely get to SCOTUS when there's disagreement between the courts. (https://www.law.cornell.edu/wex/circuit_split / https://www.law.cornell.edu/rules/supct/rule_10)
If your town passes a "no black people allowed after 10pm" law, it'll never get to SCOTUS, but it's still unconstitutional. The first level of courts it encounters will immediately overturn it.
(Two other notes: clearly unconstitutional laws tend to be a bit rare, because they're a bit embarassing when they get readily overturned. A significant portion - as much as 20% - of those 500 average bills is naming post offices; for example, https://www.congress.gov/bill/117th-congress/house-bill/203. Much of the rest are similarly void of thorny constitutional questions.)