It is a tough one, because planned obsolescence does mean that many appliances have a shorter service life and production of each machine does have a carbon footprint.
I would love to see a study that calculated out the carbon footprint of production plus carbon footprint of running so we could get a rule of thumb like, say, upgrading to more energy efficient washer/dryer is best every 5yrs because keeping an older, less energy efficient one running for 10yrs is worse overall for the planet. Some sort of way to know when it’s best to scrap for recycling ?