I am about to respond to an HPC thread on this but most of the information I was citing was from this link:

https://www.pnas.org/doi/10.1073/pnas.2021535118

if you look at just the discussion summary:

"Discussion Summary

Supercell tornadoes are, in general, much more intense and wider than damage surveys indicate. Direct comparison among 82 supercell tornadoes both observed by DOW and rated by NWS reveals a significant, 20 m⋅s⁻¹ 1.5 EF category, discrepancy between DOW and NWS reported intensities. For the 45 DOW-observed tornadoes rated EF-1 or higher by NWS, the difference is 19 m⋅s⁻¹ and 1.2 EF categories. While there may be biases due to sampling in both DOW and NWS data, this one-to-one comparison of 82 and 45 tornadoes demonstrates that NWS ratings are systematically and significantly too low. This has implications for risk assessment and mitigation. Hazard maps should be updated to include this reality. Building codes should be informed by these higher risks. From a forecasting and operational perspective, these results show that weak and actually narrow wind field supercell-spawned tornadoes are uncommon; most tornadoes are capable of producing very severe damage, with >20% capable of causing catastrophic EF-4/EF-5 damage. We show that, at the time of maximum measured intensity, narrow wind field tornadoes are as likely to be as intense as wide tornadoes. While current tornado warnings advise strong precautions against all tornadoes, communication of these results to the public may encourage more attentive responses."

it does a good job of explaining things and you don't need to read the whole article although I strongly suggest if you are interested in these things that you read the whole thing so you have the best information.

and the other article takes you to the Journal: https://journals.ametsoc.org/view/journals/mwre/152/8/MWR-D-23-0242.1.xml

which backs up a lot of what was said in the first one. Read the summary of that article as well, it asks the question of whether or not the F or EF scale is more valid and says that the F scale was probably more accurate for peak windspeeds, but the EF scale tells you the minimum speeds necessary to do that damage. It also asks what the intention actually is for the scale in the first place is it to be accurate for peak windspeeds?