Well that's just asinine. Inno gives us EBs that produce next age troops so we don't have to do a bunch of stupid quests in a stupid order and hope we don't screw up to get next age troops or above and yet won't let AO work unless both forces on the battlefield have the same age troops.
Then I have a question. Which is better on the battlefield, next age troops or AO? And I'm talking about GBG and GE specifically.
Usually AO. There are certain eras were next age troops are either situationally or regularly better than being able to crit. The AO limitation was from its creation time, when they were probably trying to give a reason to people to stop using FE troops in AF primarily.
The next era troop is generally better if:
- it has a powerful ability that your current era equivalent does not
- it has a huge jump in stats AND you're not fighting semi-easy fights (unless the extra stats are enough to regularly non-crit 1-shot, it'll be better for a long while to be able to crit 1-shot than do 9 damage instead of 8).
VF is the era that probably benefits most from next-era troops (sentinels have a huge stat jump, keen eye to replace AO without the age restriction, and flying which no VF unit has to avoid mortar).