Hindi ko alam if ito yung common practice pero I always try to separate my emails depende kung anong klaseng account or purpose ang gagawin ko.

I am using 1 email for each of this group

• Social media accounts
• Subscription based accounts (Netflix, Spotify)
• Custodial wallet accounts
• Crypto exchange accounts
• Business email

Also bukod dun sa sinabi na ng OP ito ang iba ko pang ginagawa

• When it comes to sketchy websites use disposable emails when registering - Alam ko madami ng websites na bago ka makapasok kailangan mo mag-register so the best solution just to be safe is creating a new email para lang makapag sign-up ka ang verify yung account mo.
• Always try to uncheck unnecessary options for receiving additional emails like newsletter or notifications - By doing so so are avoiding your account to be cluttered with trash and spam kung saan ka nakapag-register it's a good way of having a clean email and also lessens the risk na mabiktima ka sa phishing email na similar sa itsura na matatanggap mo, at least pag nakatanggap ka makakapag-duda ka kaagad kung bakit ka nakatanggap nun