Sarmat was not the one I saw discussed. I saw it was a variation of Topol. It has different names according to its payload. With a Nuclear payload, it could be ICBM, conventional is heavier so it travels less.
This one is named "Oreshnik" and is supposedly derived from a predecessor RS-26 "Rubezh" IRBM. You appear to be correct about range tinkering by adjusting warhead weight, which is what was demonstrated with the RS-26.
Putin cannot use ICBMs because Ukraine is TOO CLOSE for their range to be effective. The rest is true enough.
I've read the important thing about this launch was the MIRV , the multiple warheads
It's a new missile, not the Sarmat. I haven't read that it has multiple warheads, nor that multiple warheads struck a target.
Sarmat was not the one I saw discussed. I saw it was a variation of Topol. It has different names according to its payload. With a Nuclear payload, it could be ICBM, conventional is heavier so it travels less.
This one is named "Oreshnik" and is supposedly derived from a predecessor RS-26 "Rubezh" IRBM. You appear to be correct about range tinkering by adjusting warhead weight, which is what was demonstrated with the RS-26.