You have to ask yourself, is this really necessary? If you read up on what is going to be blocked they state its

Age-Restricted Content: Access to NSFW servers, channels, and commands will be blocked.
Content Filtering: Inability to turn off filters, resulting in blurred mature images.
Direct Messages (DMs): Messages from unknown users are routed to a separate inbox.
Stage Channels: Inability to speak in large-audience "Stage" channels.
Friend Requests: Potential warning prompts when receiving friend requests from unknown users


I do not think any of these thinks will actually hinder how we use the discord right now

Your mindset is exactly why companies continue to take more and more of your privacy. Let me try to explain this in a simple way.
1. The extent to which this affects the average user was deliberately left vague. Discord is, to put it very bluntly, lying through their teeth, as has been proven several times. This is and never was about protecting the children- it is and always was and always will be about collecting your data to be used against you.
2. Many CCNetters do things outside of CCNet so if they are an adult and mistakenly judged as a child by Discord's AI bot (which has been tracking users behaviour without their consent, mind you), then they're forced to send a face scan or government ID. Discord claims that the information is deleted immediately, but in subsequent paragraphs of their statements on the topic, they're very vague about the "exceptions" to deleting your picture. Furthermore, they claim that the picture "never leaves your device" which is also a lie. They themselves have said that they're using a third-party company to determine if you are a child or not with your face scan. This company, Persona, is notorious for storing and selling user data of all kinds.
3. Discord previously did something like this in the UK and Australia and promptly had a massive data breach where people's personal information, identities, and pictures were stolen by hackers. Discord claims that it was 70,000 accounts compromised but the hackers claimed it was over 2,000,000. The real number is probably somewhere in the hundreds of thousands. Why should we trust Discord to protect the IDs of children when they've already proven incapable of doing so?
4. Now for a bit of logic. Persona gets funding from a man named Peter Thiel, someone who has strong ties to Epstein. Already pretty bad. Now, Discord claims that their AI bot can determine with "high confidence" if someone is a child or not... but now they need your facial ID just to make sure? So on one hand, they know if you're a child, but on the other, they need your picture anyway if they determine that you are a child. See how that doesn't add up? If this was really as they say, they wouldn't need facial ID at all. So, from the looks of it, they want pictures of kids that they will NOT delete and will send to a third party company funded by a guy who is connected to the largest child sex-trafficking ring exposed in American history. A little suspicious if you ask me.
5. Big tech companies have been starting to use the data they gather from their users and giving it to US government agencies such as the DHS and ICE and using it to target certain groups of people. I don't think I have to explain why aiding fascists in abducting people to be sent to death camps is a bad thing.
6. Regardless of ANY of the above reasons, this is clearly just another "gimme your data" attempt by a big tech company and it's not okay in any respect. There are people who plan to quit using Discord simply out of protest, as if enough people quit using Discord after this change, it sends a message to the tech industry that people aren't okay with their privacy being violated.

I think the above reasons highlight why it is necessary.