Serious question. I'm a support main, and I've been struggling against Pyke. He seems to excel in so many aspects of the game (damage, sustain, invis, maneuverability, CC). My biggest issue is his ult. Any other support, you can outplay close 2v2's, but with Pyke, short of stopwatch or hoping he misses, once you hit 30% health you're done, and not only one person, but both of you.
These are 3 pieces of advice I can offer to help with Pyke:
1 - Poke his ADC, not him.
This is kind of like a reverse-Soraka scenario. Don't put any effort into poking Pyke but instead turn your attention to his ADC since he has no form of allied heals or shields. He can look out for himself and only himself, if his ADC is being poked out of CS or engaged on, there's not much he can do.
2 - **Back off when you see him charging up his hook. **
This sounds like it would be common sense but I see a lot of people try to challenge Pyke when he's charging up his hook. If you see him start up a Q back off behind minions or move away from him. If he's closer to you, try and move side-to-side rather than running directly away.
3 - Shut him down with heals, CC, and MS.
The best way to beat him consistently is through playing an Enchanter like Sona, Yuumi, or Nami. (doesn't have to be those particular three.) Enchanters have the tools and skillsets to beat him at almost every stage of the game. Likewise, Tanks are the worst into Pyke unless you're very skilled since they take a while to come online. Pyke's early game isn't the greatest, but Tanks are worse and he can use that early-mid spike to dominate the rest of the game.
Heals - Pyke's only option is to all-in, he's not going to be poking you down and his ADC will usually be more focused on CSing and following up on his all-ins. You can discourage his all-ins by staying at medium-high HP. More importantly, save your heals to raise allies out of his ultimate threshold. A well placed heal (be it from summoner Heal, an ability, or even something like Triumph) is the best way to stop Pyke in his tracks and kill him. If he mistimes his ult or you bait him into using it, you can follow up with CC and burst him down.
Shields - Pyke's ultimate goes through shields, but a well placed shield can still stop you (or your allies) from being dropped into ult range. Shielding is important, especially in teamfights, but you should be prioritizing heals above all else.
Vision + other tidbits - Exhaust doesn't work too well on Pyke. He himself does a surprisingly low amount of damage and exhausting him will not reduce his ultimate threshold, consider taking Ignite or even double Heal. Ward up midway through river and near your tri-bush, that way you can see him when he's coming from behind and stop him from roaming mid. Most importantly: MIA ping. Let your team know when he's away from lane, because if he gets a good roam off you and your midlaner/jungler are going to suffer for it.
edit: And I didn't really mention these because I assumed you already knew, but buying armor and control wards help a ton. Armor weakens his already lower damage output (and that of his ADC) while control wards discourage him from roaming and can shut off his passive.