What is in it for the maintainers who would then have to support hardware they do not neccessarly have access to, adding development time to the linux kernel ma

What is in it for the maintainers who would then have to support hardware they do not neccessarly have access to, adding development time to the linux kernel maintainers who honestly would be better off spending their time improving linux further instead of supporting potentially thousands of users at best? Imo the responisibility lies with the hardware vendors. Sell your hardware with working software, and support it for x years guaranteed. When the support period ends they can decide to extend it (they wont, but they could) instead of relying on developers who have nothing to do with the product and are working for free for the hardware vendor. Either that or contract kernel maintainers to upstream it for x years and they do the heavy lifting, but that's always going to be more expensive than doing it in-house.