I've been looking again at the Welsh Government's own spreadsheets on accident data from 2021 and 2022. Feel free to download them from
https://statswales.gov.wales/Catalog...ent-Level-Data
2022 - number of accidents on 30mph roads across Wales that resulted in fatalities or serious accidents - 2.
2021 - number of accidents on 30mph roads across Wales that resulted in fatalities or serious accidents - 3.
2020 - lockdown
2019 - number of accidents on 30mph roads across Wales that resulted in fatalities or serious accidents - 2.
2018 - number of accidents on 30mph roads across Wales that resulted in fatalities or serious accidents - 2.
I haven't researched them all, but one accident in 2022 was in the Gower where a car drove into a petrol station where, I'm pretty sure, a reduction in speed wouldn't have made any difference.