No. Decarb makes it runnier
You’ve got viscosity right.
we are agreed that removing solvent increases viscosity
and that Heat decreases it
If you have empirical evidence of viscosity increase on decarb, then it is because of the solvent you’re driving off…removal of the carboxyl group as CO2 from THCA to THC absolutely reduces the viscosity.
‘‘Tis why we decarb shatter to make pens…
and why year old barn find will only ever make pull & snap, never shatter.