Yes, but it still ended the polio epidemic resulting in a drastic drop in total polio-related deaths.

You don't get vaccines in use for 50 years without vaccines in use for 1 year, and you don't get that without using them for 6 months, and you can say the same about COVID-19 vaccination. Arguing otherwise is just failing to understand linear time.

There can be understanding, but nothing really beats mass numbers of doses over multiple years to generate it.

The safety factors of a vaccine become better understood over time and use, and you can say the same about COVID-19 vaccination.

You should conclude that COVID-19 vaccination - even the early versions - had net very good outcomes too, unless you're a wilfully ignorant conspiracy theorist.

The bar isn't "perfect vaccine", the bar is "significantly better than no vaccine". And this depends on the urgency of the situation.

The only "debacle" is a political/sentiment one, the mainstreaming of crankery, especially in the USA. It's now a full-fledged systemic public health anti-vax debacle.

But MRNA vaccines are a significant new medical tool, not just for COVID-19, not just for viral diseases.