I don’t know what “Health Feedback” is, but they are mistaken.
The quote you gave first links to the article I was referring to in the “behave very differently” hyperlink. It says nothing of the sort, as I said.
https://www.ahajournals.org/doi/10.1161/CIRCRESAHA.121.318902
The second hyperlink “fragments” links to this preprint paper.

SARS-CoV-2 mRNA vaccines induce a robust germinal centre reaction in humans
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) messenger RNA (mRNA)-based vaccines are ~95% effective in preventing coronavirus disease 2019. However, the dynamics of antibody secreting plasmablasts (PBs) and germinal centre (GC) B...
It also says nothing of the sort. In fact, it also says nothing about “cells mostly break down the spike protein into fragments” which your article claims it did. The researchers in that article broke up the collected spike protein in vitro to assess for mutations in collected samples. I’m not sure if that’s where their confusion came from.
Secondly, the spike protein generated by a Covid-19 vaccine doesn’t assemble into new viral particles, unlike the spike protein from SARS-CoV-2.
The spike protein from SARS-CoV-2 does not “assemble into new viral particles.”
Thirdly, the spike protein in Covid-19 vaccines is genetically modified to enhance the immune response and to stop it binding to cell receptors in the same way the SARS-CoV-2 spike protein would.
The “modifications” used in both the mRNA-1273 and BNT162b2 were to prevent their degradation once they arrive in cells. They both encode for the at the time wild type spike protein.
viruses-13-00109-v3.pdf
3.22 MB
So again…the vaccine did not alter the spike protein or remove the ACE2 receptor component. Both mRNA vaccines encode the entire spike protein, including the RBD which binds to hACE2. You can check RBD specific titers after vaccination.