9700K is still solidly faster in per-thread performance. Having SMT gives the 3700X a boost in total performance though. The 9900K beats all the 8C Ryzens (including 3800X) and beats the 3900X in per-thread performance but loses in total performance (of course).
Real-world test with mitigations:
https://www.phoronix.com/scan.php?page=article&item=3900x-99...
Or https://www.techpowerup.com/review/amd-ryzen-7-3700x/22.html
9700K is still solidly faster in per-thread performance. Having SMT gives the 3700X a boost in total performance though. The 9900K beats all the 8C Ryzens (including 3800X) and beats the 3900X in per-thread performance but loses in total performance (of course).