All of these things you've identified here appear in the syllabus I attached above. Note names on the stave in Grade 1, along with longer note and rest values. Time and Key Signatures, along with shorter notes through grades 1 to 5 in increasing complexity. No doubt you also learned about dynamics/articulation markings, phrase marks, repeats and voltas, the meaning of con sordino and senza sordino, etc... To say you acquired no theoretical knowledge is, I think, doing yourself some level of disservice. You nor label these things as 'theory' and just see as 'things you know', but they are all necessary for the correct analysis and execution of a score, you got the ability to read from somewhere, and they are clearly part of music theory, IMHO.
I'm gonna split that hair and say to execute music in anything except the most organic ways (I.e. teaching yourself what sounds good), you do have to know what's going on at some level.
But my point always is, the theory drives the sight reading, which is what you seem to be saying and I agree with that.
Sight Reading does not in any way, drive the theory. That is the questions the OP posed. My performing the act of sight reading did not gain me any theoretical knowledge or insight. It was just a skill that was performed. I could be wrong in interpreting what you are conveying.
I think we need to, and can, agree on the following thesis:
From the starting point - where you know exactly zero about theory - to the point where you're competent enough to do sight reading, your knowledge about musical theory has increased significantly.
So, to a point the answer is yes. You cannot not learn anything about musical theory while learning sight reading.
At the same time, however, you're barely scratching the surface. You're reading dots off a sheet of paper and translate those into noises you make with your bass guitar. One could say you've learned all the letters of the alphabet but you're reading them one by one. You know zip about grammar.
Imagine a first grader reading off the blackboard, forming the words letter by letter.
Now take a grown person that knows the whole word with barely a glance, often even able to finish a sentence after reading the first half.