Using different emails for all your accounts is great for keeping you safe online. Not only does it make you very organized and methodical, it also keeps the online identities associated with them separate.
For example, if you get an email claiming to be from your bank but the email goes to your social media email, you know it’s fake.
Another great use of multiple emails is having a dedicated email address to sign up for apps you want to try, but which might have questionable security or might spam you with promotional messages.
For extra security, you can try using a different username every time as well. Now anyone trying to get into your account must guess both the username AND the password!