When it comes to training, if someone wanted to argue against my position by questioning the credentials of my scientific education perhaps they could be persuasive.
If someone was more interested in taking part in medical research/sciences and also discussions of policy relating to them I could have quite constructive conversations I expect.
At some point, assertions like "[COVID] vaccines are ineffective" need to be challenged (which? over what time frame? where's the data?) or they become "everybody knows ...".
"[COVID] vaccines are ineffective" is a fair assertion if the standard of something being 'effective' is preventing getting infected at all.
A better way to challenge the validity of that assertion is to make more effective COVID vaccines. In my view, bypassing the stage of creation of spike proteins and more directly getting the cells able to produce the relevant antibodies when needed would be a better vaccine, possibly more effective. It would also likely be safer (as the spike protein itself is dangerous, and the immune response to it can also be dangerous, by the sounds of it when the vaccine has not stayed localised in the arm but moved to the heart), so a vaccine that has solved that issue would do better when looked at in terms of a risk / reward ratio.
"[COVID] vaccines are effective [enough to be worth the risk of side-effects]" is something that would be better addressed through improving the vaccines themselves, possibly through improved public messaging, but I don't think as yet the data is there that supports that in an unequivocal way, and improved vaccines with greatly improved efficacy and safety which are then accurately described would be the best way to get the message accross.
Something can be ineffective compared to something else. Such as a COVID vaccine being ineffective compared to some expectations or representations of it.