I bought my iMac M3 December 2023. So it's coming up to 3 years in December 2026. Yes I'm fully aware of that sudden screen failure as I've posted that link from the Apple Community Forum that Apple closed! They closed it as more and more M1 iMac users are reporting this failure within the 2 year mark of iMac M1 users.
Users complain of horizontal lines appearing and staying on the screen about two years from the date of purchase.
www.tomshardware.com