Yes, but a bunch of the early magazine-fed rifles - like the SVT-40 and G43 - retained stripper clip loading as an alternative option, as militaries of the time weren't quite confident enough in magazines. This turned out to be a sensible concern in WW2, as both the Soviets and the Germans struggled to actually produce sufficient magazines, and in practice most soldiers issued those rifles ended up keeping just the one magazine permanently in the gun and topping it off with stripper clips. This directly influenced the design of the SKS, which forewent the detachable magazine in favor of a fixed one, as they anticipated running into the same issue as the SVT and decided to skip detachable mags as an option altogether.

Other post-war rifles like the MAS-49, FN-49, the vz. 58's own predecessor - the vz. 52 - and some FN FAL variants also featured stripper clip loading

For the vz. 58 though, I always felt that late '50s was rather late for the Czechoslovaks to still be hanging onto this idea, the AK was starting to be issued pretty widely at this point without much of a problem in magazine availability, and of all the non-Soviet Warsaw Pact countries Czechoslovakia was arguably the strongest industrially (East Germany & Poland may have been had they not gotten their industries razed to the ground during the war, so they had to rebuild a bunch first, unlike the Czechoslovaks whose industry survived relatively unscathed and was pumping out gear for the Germans pretty much until the end), but I guess they were still worried.