This isn't a story about side effects being "far worse than portrayed" it's one about +/- 4000 people whose claims have yet to be processed. That may or may not be a scandal but it is not evidence of a cover up of vaccine side effects. Up to 53,000,000 people have been vaccinated. 4000 represents, I think, 0.000075% of those vaccinated. I don't know what the norm might be for any given treatment but under the circumstances this is a tiny number. Personally I've experienced side-effects of a long standing drug, Ramipril, nothing serious but a side-effect all the same. 1 in 100, 1%, of those prescribed can have one or more of seven minor side-effects, there are eight serious side-effects but I don't have figures on those. Modern medicines are not without risk.
It's your statement which is misleading
https://coronavirus.data.gov.uk/details/vaccinations