Realistically we are talking about expecting support for decade old products in the tech industry here. At no point in the history of tech was this ever thought as reasonable. We are talking about manufacturers going back to 9-12 yr old products to make updates for what are, at best, edge cases.
If you are using something that old, you are obscure, therefore less likely to be hacked. If you are using good security practices, that is a good second layer of security, on top of obscurity.
If these old machines are your daily driver, and you are worried about security, then you ought to upgrade. There is only so much you can do to secure an old system running old hardware and old software. They are like straw huts compared to newer homes made of wood or brick. There is only so much you can do to make a straw hut secure.