Sword fights certainly could seem more realistic without losing the excitement. Check this out ('fighting' starts at around 2 minutes): https://www.youtube.com/watch?v=4GoQlvc_H3s
Yes it’s interesting as a YouTube video, but for filmmaking suspense comes from “dilating” the moment in time, spending as much as possible in each step before the final blow.
With realistic sword fighting, this is mostly impossible afaik.
Tanner Greer recently posted about teaching the Iliad to high schoolers, and made this point explicitly. The Iliad is composed for an audience that is familiar with hand-to-hand combat, and depicts it exactly this way: two people close, and one of them kills the other one and moves on. Fighting is mostly done with spears, not swords, but it happens the same way.
Homeric depictions of combat impressed my mother in a different way (she is a doctor): "Wow! Homer really knew his human anatomy!"
https://www.youtube.com/watch?v=TvVyyH2mQ9E
Also, the sword fight from "The Deluge" (Polish title - "Potop"). Admittedly, the plot says the commander didn't want to kill a rebelling but skilled officer, just teach him a lesson. But otherwise well done. It was a time when fencing and horse riding training was mandatory for Polish actors.