Why Pyke is having trouble as support (spoiler: he has a big size Relic Shield)
Besides the fact that he's new and that people obviously need to get acquainted with his playstyle, there is something else that particularly characterizes him and that I want you to realize, and that is one of the main things that are making him somewhat underwhelming. Again, it's not the fact that he's an aggressive melee squishy support, because we already had Rakan who had the same issues at the beginning, before people realized how to play him. The problem is that Pyke has a big size Relic Shield as his ultimate. As a Relic Shield user, have you ever tried going into mid-late game without proccing it even once? You will definitely feel the difference in gold. That's why Pyke is particularly hard. Since this built-in Relic Shield supposedly covers a significant part of his kit budget, he works with the idea of the gold lead: this means he is a snowball-reliant support that not only needs takedowns in early game to stay relevant, but he actually needs to execute with his ultimate to proc his "Relic Shield" as well. Since, again, as we already know with champions who have stacking or similar mechanics, these are not actually bonuses: at the beginning of the game champions are bound to fulfill the special conditions of their kits, otherwise they end up being much weaker versions of themselves. After a certain number of executions the bonus pays off for its budget cost, and after that point it becomes a full extra bonus. But before that, they are reliant on fulfilling these conditions. An easy example is Sion: a Sion that hasn't killed any unit at all and hasn't stacked his passive will have one of the lowest amount of health for a tank. It's only after he has stacked enough hp that he starts seeing an actual bonus. Pyke is the same: Pyke is reliant on proccing his ultimate's gold bonus a couple of times at the start to become even. After that it starts becoming an actual bonus. And since this condition is not actually that easy to fulfill and it depends on players' confidence with Pyke's kit itself (which, at this time, hasn't been built yet), Pyke is bound to have such a low impact as a support, much lower than expected for a new champion.
200 health (7.145% Bonus Health Conversion to AD) = 14.29 AD
350 health (7.145% Bonus Health Conversion to AD) = 25.007 AD
or
who essentially hard counter the squishy assassin style support by being able to catch him out if he goes in or early game simply engage on pyke's adc b/c if pyke isnt fed he wont have the damage to assassinate the enemy adc w/ just his damage.