Note I'm simply trying to guess what the market consensus is made of, personally I'm just holding a leveraged long position and I am not so confident at the moment it'll work out well.
As to buying now vs then: no, this isn't a clear choice. Back then Tesla didn't discredit itself as much by missing its own guidance, folks were actually hopeful they learned from Model X disaster. Turned out, they didn't quite do that. They overspent on automation (wasted money and effort, some auto production expert commented that $2B spend on production line is unheard of), they had to stretch their finances and they are in a less advantageous position now vs. what was anticipated a year ago. Sure, the uncertainty of when M3 ramp happens is resolved, but for valuation to go up on that we would have to assume that valuation was based on an even more grim forecast (say, 5K/month 3 month from now) than what reality delivered.