The so-called 'drop suits' of the early 22nd century were the result of not so much advances in surface tactics or materials engineering as applied biology. While the idea of inserting surface-mobile combat assets from orbit had been attractive for some time, the limits of either pilot physiology or telepresence made this difficult in practice. Manned units were subject to deceleration limits that increased approach time and made them vulnerable to ground defenses, while remote units were vulnerable to control lag as well as link spoofing. Autonomous AIs were also not suitable, for both technical as well as political reasons.
However, with the passage of the Sapiency Acts in 2206 the modification of human genetics became a matter of practical concern once again. It was revealed later that many of the Ninth Wave programs had never actually been terminated, but rather moved offworld. Theoretical fears aside, it meant (among other things) that it would be possible to modify pilots to withstand the g-forces involved without jeopardizing their legal status. Typically the suits were carried externally below unmanned booster and weapon packs, but many configurations were possible.
Here we see the 'Daisy Pusher' a Block 10 'Mephisto' suit being used in operations against Trans-C Separatists on Titan. The terraforming of that moon served as a sort of mirror for the strange civil war that wracked the settlements there. The conflict was noted for both questions of sapiency, humanity, and the moral weight of aesthetics.
Naturally, none of these questions were decided to the satisfaction of anyone involved.