Poppy Nerfs - unintended consequences

I understand the nerfs to Poppy and why you did them, but I think you forgot a pairing of events that caused a bigger problem.

The change to the duration of Iron Ambassador passive was a mistake. It limits engages and pushes her into a poke role like you'd expect some of the dps type toplaners to be vs a tank but then reduces her effectiveness as a tank during team fights as well. Changing the passive and making it's duration shorter for the early game isn't entirely out of bounds as the scaling doesn't show up as a problem until later in the game when you're making engages as a tank. The problem I've noticed is that as your health pool grows you end up wasting more and more of your shield due to the shortened length, when you combine that with trying to make sensible shield stacking engagements you're left standing around doing nothing in a team fight because you don't want to stack it with your Colossus shield or you'll just end up wasting all or most of it. So you engage, E>Q and then you cannot follow up with an auto for some time and in many cases if you're running gauntlet your spellblade will drop off so you have to re-engage to get it back. In other words, the thing you want her to be good at you removed her from doing because of shortened tank buff duration and you removed the majority of her dps from the opening of a team fight because if she has to tank she has to use her shields more wisely. Its a big contrast to other tanks which can freely engage at will and do all the damage they want whenever they want and suffer no consequences. (Later on I'll talk about how the Steadfast Presence passive creates another problem)

This becomes a problem in laning and 1v1 situations with the combination of lifesteal and damage several champions get you need to do a lot of burst but you also need your survivability to last or you just get rundown lane now because the cooldowns on both of those shields is relatively long in situations vs sustained dps champions. You very literally created a situation where you are a tank and you're meant to engage but you have to poke because nothing you have hangs around long enough to matter and you reduced her kill pressure significantly because of it.

The Stubborn to a Fault portion of her Steadfast Presence passive is another colliding event that creates a problem. If you buy through with just health/armor items to gain the ability to have a substantial amount of health while under that 40% health threshold you end up wasting even more of your shields during small engagements due to the shorter duration.

All of these problems combined means that you reduced her tanking effectiveness and kill pressure to the point where her build needs to move into more of a top lane bruiser builds where you are punishing people in short fights like a poke champ and also you can't sustain in lane vs damage champs as a tank since you can't punish them immediately and you don't have ready access to shields anymore because they all drop off nearly by the time your stun duration is over. This means you can only poke realistically every 30 seconds and by then all their life steal or just natural regeneration even has healed them up. Even those situations are limited because you can only half poke because you need to save your Passive for disengage because lane opponents will immediately counter engage and do such ridiculous amounts of damage even with no armor pen you'll get chunked out more than you did to them. This isn't just a Poppy problem either. This is a full on tank problem, the recent meta changes have made pure tanks nearly unplayable aside from Jungle roles and it's showing.

I don't know how to fix the problem but I can very easily see that there is one, especially vs duelists who win in lane and just dive backlines in team fights and murder everyone, including the tank because they get a huge lane advantage and it turns into a huge whole game advantage.

EDIT: I didn't openly mention it cause I thought it would be implied but it also creates a lane disparity problem that translates into being behind late game making you weaker overall and then on top of that puts you behind in gold and in some cases experience.