Nowadays, with powders currently available, handloaders can almost match factory .300 Win. Mag. with a .30/06 as long as it has a 24" to 26"bl.
Hornady's Annual Manual 2023 has this data.

This puts the .30/06 ahead of the 7mm Rem. Mag.
I've owned a couple 7MM Rem. Mags.(& a chronograph) - was not impressed.