I spent some time in the Lyme disease communities after I tested positive for Lyme disease under the official two-test CDC criteria. The pop-culture version of Lyme disease discussed on the Internet has almost no resemblance to the actual medical science. There are a lot of people genuinely suffering unexplained symptoms, real pain, who are drawn into the seductive explanations of the “chronic Lyme” communities onlin…
I don't think it's possible to make an absolute statement like this with 100% certainty given the current state of the art. Lyme is a spirochete, and there also seems to be real research suggesting it can grow biofilm to make it antibiotic resistant or resurgent.
There are patients who test positive under CDC criteria, take antibiotics, and never see a transition from IgM to IgG.
There are also patients who test postive under CDC criteria, take antibiotics, see a transition, but still experience symptoms (what you would call 'long-lasting effects'). In some cases patients in that situation have extreme gland swelling that when biopsied, seem to contain Lyme.
Like all of medicine, I think it's squishier than what you're describing. There is also a lot of crazy shit on the internet, but like you say, that's because people are genuinely suffering and have no alternatives.