Quoted from PinMonk:
I wonder if the very early ones were using playfields that had been sitting in the warehouse curing for months and months during COVID-19 lockdown, a luxury ones that came later didn't have.
I imagine that the amount of bad play fields with the issue is actually fairly small. They’ve shipped 100’s already and we’re only hearing from a vocal minority. They have every right to be vocal but the ones having no issues are probably enjoying their game not posting how perfect their playfields are either.