Not really. Because Gems are flexible and you can reroll affixes.
Try to get items that have the other 2 affixes you want (Life/Armour/MStat) then roll for resist. Even assuming they are equally likely, you are more likely to get a good roll on a single than All Res because there are 5 possible affixes instead of just 1. At most you need 3 different ones on your main armour pieces, then you fill the gaps with gems and consider even using your amulet and rings if you need to.
With a bit of planning, getting 5 good single affixes is easier than getting enough all res. That’s not to say that if you get lucky with some decent All Res rolls you shouldn’t swap to that - you absolutely should as the way it is right now All Res is more efficient. But definitely harder to achieve until you hit at least 1 big All Res affix, either through GA or a Unique.