You might not have noticed what you've done here, but you've not only agreed to corporal punishment for children but also for harsher corporal punishment for criminals across the board. Read the whole conversation chain and reflect on how bad the optics are. There is a reason why your stance is unpopular.
"Spanking looks like an 8/10 on the subjective harmful scale, but actually on the objective harmful scale its closer to a 3/10. We must rectify the bad reputation of spanking!" is not the type of motivation that should drive pedagogy research.
If you're saying we should pretend that spanking is worse than (we currently know) it is, then I don't agree.
I haven't said anything about corporal punishment for criminals, and I don't know of any evidence for or against it - that strikes me as a very different argument, partly because the level of violence is likely to be much greater.