How necessary are irradiated tablets?

For a while I've been running 6-mod waystones, but I've been dying more and more lately and without having a revive available it's kinda kicked me down to only using 4 or 5 mod tablets.

Normally I run an irradiated tablet and two others for whatever mechanic I want, but since I only have two slots now that isn't an option- is it necessary to keep an irradiated tablet on all the time to get good drops, both currencies and equipment, or should I just use two different mechanic tablets?

They're not necessary at all in general. The only thing they're truly necessary for is farming ilvl82 bases, which requires T16s and irradiated and a powerful boss alongside the atlas point that adds a level to boss maps. I think maybe also to get lvl 19 and 20 gems.

The extra level is a multiplier to loot. But overall not failing a map is way more important than anything. It doesn't matter if the irradiated tablet adds 20% more loot if you brick the map 2 rare monsters in.