I created this account just to comment this.
I do believe there is value to come from creating a webhook for Aternos for the convenience. I am always on Discord chatting up with my friends and I typically do not have Minecraft or the Aternos website up. I'm sure there are a lot of people the same way. For those that are already on Discord, they no longer have to turn on Chrome and get to the website.
Especially for weaker computers like Macbooks where having browsers, Discord, and Minecraft open will drain it a lot and be especially slow, this removes those steps.
Plus, depending on how each individual sets up the webhook, getting a notification that a server is on may prompt them to start playing. Without it, they may have completely forgotten about an Aternos server.