Yeah the 21" sun monitors we had in school were trinitron. I remember they were heavy for a 21" monitor (shielding?) and the degaussing on startup would induct into an adjacent monitor. (I was a sysadmin for a Sun heavy CS department in the 90's.)
However, aperture grilles also use differently-shaped glass from shadow masks. The screens are only curved horizontally like a cylinder rather than on both axes like a sphere. This requires thicker, heavier glass to hold the vacuum.
Later flat-glass shadow-mask tubes were much closer in weight to flat Trinitrons.