Because I felt like most of what happened while the game was still competitive was correctable, and that they actually stood up and made some stops in critical situations but the offense did absolutely nothing to help them out. The run defense was also pretty solid while the game was competitive, Deebo had like 2-3 solid runs but McCarthy was mostly under wraps.
A lot of the issues early on were penalties, giving up the trick play, allowing a screen to pop on 2nd and 12 and so forth, those are things that can be corrected and/or aren't systemic.
The only drive that really pissed me off was the opening drive of the 2nd half when it was 21-10 and they gave up a 3rd and 12 conversion, although on that drive Purdy was just locked in and making some ridiculous throws after not being forced to do much in the first half because they could afford to play at their pace and rhythm without being forced into high leverage situations.
Like yea, they gave up some plays obviously but the dam is always going to break when your offense is going 3 and out 85% of the time.