Um yeah. That would be why in NFL history, of those that have completed 35 or more passes the record is 58-89. For the playoffs, the record is 16-24, with Brady’s 4-0 skewing the results from being even more contrary - of the top 7, only Brady has a win.
Probably the most ridiculous regular season result is Warren Moon completing 73% (41-56) of his passes for no TDs and no Interceptions....though his team had one of the relatively few wins.
Teams behind throw more, so yes QBs racking up lots of completions tend to be on losing efforts. But you commit the fallacy “just run 25 times” when you take that to mean completing passes doesn’t lead to victory. It’s not necessarily the raw number of completions, it’s the percentage. Tebow completes less than 50% of his passes. That’s bad. Period.