Not quite accurate about the Israeli data, which were published in a pre-print two days ago. The 4th dose of the Pfizer vaccine showed a peak efficacy of 64% during week 3 of the study, declining to 29% by the end of the 10-week follow-up period. Protection against severe disease (defined as requiring hospitalization or death), was good, but severe disease was also rare among people who had only received 3 doses. One caveat is that the study population was aged 60 and above, and results in younger people might be different.
My take is that a 4th dose of the mRNA vaccines will be offered in other countries. However, uptake will be low, as is the case for "booster" shots. It's doubtful that anyone who would accept a 3rd dose would change their mind and take 2 more.
My greatest concern is that in addition to patients who experience prolonged, debilitating symptoms, we'll increasingly learn that people who experienced mild episodes of COVID-19 will be prone to a variety of neurological, cardiovascular, endocrine, and other conditions for the rest of their lives.