As for the definition of 'important,' tonsils are like bouncers at the party that is your body - they keep an eye out for troublemakers and do their best to toss out any pathogens that try to crash the scene. Tonsils help activate the immune system and condition white blood cells for pathogens in the environment.
If you want an actual study, here is one example:
>Conclusion: Overall, according to these findings, CD10 as a marker of B lymphocytes in children undergoing tonsillectomy was significantly less than those healthy children. This may indicate a decrease in B cells and further reduced antibody production in these patients.
I'm not sure I can begin to answer that question given the immune system's complexity... How many percent smarter does your frontal lobe's top left corner make you?
If you have to leave in most of an organ for it to function, then it's a lot more important than an organ where you can chop out the whole thing with minimal consequences.
I don't understand why you are so invested in this argument, but I'll tell you this much: This is something I have witnessed personally, and the effects are pretty bad.
> I don't understand why you are so invested in this argument
I have so far typed four sentences, so I have no idea what you mean by that.
> This is something I have witnessed personally, and the effects are pretty bad.
Are you talking about tonsilectomy or brain damage?
Because I'm saying that losing a corner of your brain is more important than losing your tonsils. If you have evidence otherwise I'm open to hearing it..