Because all that good stuff was bundled with the trigger provisions. When I asked - repeatedly - everyone on this board if they would accept a bill with a trigger level of zero the answer was a resounding NO.

Only the asylum moratorium was bundled with the trigger. And the reason why you got a resounding NO is because there are very good arguments that the asylum moratorium isn't just good stuff. It's very likely a violation of our treaty commitments, and very possibly a violation of international human rights, to refuse to give a refugee that might be facing persecution even a hearing. So you need to build in some justification for why the U.S. is suddenly willing to violate international human rights provisions. Hence, the trigger. Unfortunately, immigration hardliners went out there and started misrepresenting it as codifying some number of migrants who get to come into the country (when in fact it was based on encounters, which would include even the folks who were summarily deported through expedited removal).

I'm okay with that, because democrats like Smith-Members are potentially capital-D Democrats you can do business with.

It doesn't matter. If you signal that you're not willing to do business - that you won't accept any bill other than your messaging bill - then no one's going to try to do business with you.

Just as with the Freedom Caucus in the House on the right, it doesn't matter whether you gain or lose a few centrist House members.
Unless you're in a circumstance where you can force the party base to swallow a bill they hate, it won't get passed. You passed up a once-in-a-few generations opportunity to get the Democrats to force the CPC and the rest of the immigrant advocacy caucus to eat an "all wall, no door" immigration bill that didn't even include DREAMERs. And you walked from it, with fantasies in your head that there was a better deal some day down the road. Sheer folly, if what you actually want is a change in U.S. border policy.