Hardware + OS + Software is an interrelated system. None of those pieces work independent of the other. When one changes one of those items, its relationship to the other items change. Examples:
New Hardware -> New minimum OS version -> Software updates required for compatibility with hardware + OS combination
New OS -> Support for older hardware dropped -> Some older software no longer supported due to API changes
New Software -> Support for older OS dropped due to changed/removed APIs, or to take advantage of new APIs
And so on, and so forth. As others have suggested: The only way to not have to pay attention to these relationships is to arrive at a stable arrangement of all three then stop upgrading all three. This, however, comes with its own set of trade-offs and risks in terms security and having no "plan B" if the hardware you're using fails.
New Hardware -> New minimum OS version -> Software updates required for compatibility with hardware + OS combination
New OS -> Support for older hardware dropped -> Some older software no longer supported due to API changes
New Software -> Support for older OS dropped due to changed/removed APIs, or to take advantage of new APIs
And so on, and so forth. As others have suggested: The only way to not have to pay attention to these relationships is to arrive at a stable arrangement of all three then stop upgrading all three. This, however, comes with its own set of trade-offs and risks in terms security and having no "plan B" if the hardware you're using fails.