One-hundred-nanometer-gate (Al,In)N/GaN high-electron-mobility transistors (HEMTs) grown on semi-insulating SiC achieve a maximum current density of 1.84 A/mm at VGS = 0 V, an extrinsic transconductance of 480 mS/mm, and a peak current gain cutoff frequency as high as fT = 144 GHz, which is the highest so far reported for any (Al,In)N/GaN-based HEMT. This fT matches the best published values that we could find for 100-nm-gate (Al,Ga)N/GaN HEMTs, thus closing the cutoff frequency gap between (Al,In)N/GaN and (Al,Ga)N/GaN HEMTs. Additionally, similar devices grown on (111) high-resistivity silicon show a peak fT of 113 GHz, also setting a new performance benchmark for (Al,In)N/GaN HEMTs on silicon. Our findings indicate significant performance advantages for (Al,In)N/GaN HEMTs fabricated on SiC substrates. The improved performance for devices grown on SiC is derived from the superior transport properties of (Al,In)N/GaN 2DEGs grown on that substrate.