Energy Shield regen counterplay after Frost Bomb nerf in 3.23

Please help me - how to play against heavy ES regen mobs/boss when 75% ES regen is removed from Frost Bomb. Some bosses seams immortal after nerfing the frost bomb in the comming patch - for example Omnifobia/Kosis and runic monsters in expedition with taking many stones (ward + reduced damage taken + elemental resist + no crits) + regeneration ES in 3 sec or sth like that. I'm also very curious how to play in the Hall of the Grandmasters against ES regen withoug frost bomb now.

Please help becaus I have now idea what to do now against ES regen now.

- Helmet implicit for less regen on hit
- recovery mastery for 50% less regen on hit
- pantheon for 50% less regen for nearby enemies
- potentially: one the new charms might grant a watered down version of occultists void beacon ascendany for x% less regen nearby


There are plenty ways to deal with this issue

What was the reason for changing from 50/50 to 75/0?

I haven't been having a problem with this but I don't understand why it was done? The option above are all good but not always practical for some builds particularly in ssf/ruthless. I've been using frostbomb regularly on low dps builds for some leagues now, not sure why this would be changed to only work on life and no es?