You're both right but you're downplaying the significance of the youth. Tiktok exploded off young people and is the most popular platform today. We'd been trending that way but the fashion world bent a knee to the Y2K designs they pushed, Ed Hardy shirts are popular again because of the youth. They're the culture setters/tastemakers
You always make sure the platform or whatever is accessible for them, they're the ones most easily manipulable and accepting to new routines. Get a cult following with them and they'll make sure the older generations know who you are. When they start looking for the new flash in the pan the idea is to have enough of them plus the older brackets to survive then thrive. If you're bigger than you were before they left many will come back once other flashs flicker out because they're already familiar with your brand, adaptation is the key
You don't need a Twitter account to start/run a business, it's mandatory you have a IG and Tiktok. You could probably get by with just TikTok, that's how many more eyes are on the platform than IG, but IG's just better for intimate communication. The youth have passed everyone but millennials in luxury spending so imagine if they had the wallets older gens had. 18-24 is one of if not your most important market if you want to make money/have a solid platform and they don't use Twitter that much except to make stan accounts