Just saying the team didnt live up to expectations and he didnt exactly light the world on fire either. 59 Tds in 3 years. Not a lot of production at a very big school in a sub par PAC 12. Im honestly surprised he got drafted as high as he did. I know stats and QB records dont tell the whole story but that has followed him into the NFL. His lack of production and his teams under performing are relevant as much as most dont want to hear it.
At some point you have to produce. It cant be all "talent" and potential. because the talent hasnt produce anything yet.
UCLA may be a big school in terms of square feet but they are nowhere near a relevant power school. This is a school that has 1 top 10 finish (2014) in 20 years, the last time before that was 1998. They haven't played in one of the 4 major bowl games since 1998 as well. For some perspective on how irrelevant they have been the University of Central Florida has had 3 top 10 finishes in the last 10 years and has played in 2 major bowl games in the last 10 as well.
Even if he had 40 TD's at UCLA and won 1 or 2 national championships it would still be just talent and potential since those things don't guarantee anything in the NFL. You're right though at some point he does have to produce in the NFL but to expect that point to be someones rookie year makes no sense. Judging by your username I assume you've watched football since the 70's which means you should know the majority of rookie QB's have bad rookie seasons.