Speculations Sommers not being able to regenerate is not permanent.

[sanjikun]

I think it's just ACoC.

 

[Vanlax]

you didnt get any lightning when sommers lost his hand either. its almost like the conquerors haki isnt the lightning part

Well the AdvCOC we know is Conquerors Coating which was introduced as having lightning trails.

Maybe COC was used indeed but invi, like Ashura was hinted by Kaido to be COC as well. Maybe similar also to what was used in Zoro's slash vs Monet. Maybe COC was used, just not the COC Coating introduced in Luffy's fight vs Kaido.

 

[Jailer]

Or the HK regen is a lower tier version of the elders crazy right

You just made this up, Gunko's entire upper half was eviscerated and did regenerate fully

 

[Jesse Pinkman]

If you see Gorosei also have scar marks and even with immortality it didn’t go away . So whatever Gaban used on Sommers will likely not generate .

This is very likely because of the different form of Haki Gaban has used I suspect it’s another advanced form of Haki the likes of how Rayleigh was able to disarm the blast around Camie .

 

[Levi]

You just made this up, Gunko's entire upper half was eviscerated and did regenerate fully

By uslop so it doesn’t mean much while luffy could barely even scratch Saturn with advco.
ju peter entire head was chopped off and it came back
elders>>>Hk