It's to judge it based on the value it gives you per unit of time.
It's the entire justification for investing less in things you use less, and investing more in things you use more. That we generally receive benefits not in one-offs but spread out over time.
Something might not sound so expensive if you frame it as $0.50/hour of use. But it certainly does if there's an alternative that meets your needs that you can get for $0.10/hour of use.
There have been a bunch of times in my life when I delayed purchasing or felt guilty about purchasing something genuinely valuable but very expensive.
But then when you're in year 5 or 7 of using it daily, you're like... best use of my money ever. That's the point here.
If you spend a ton of time needing a large screen, using this for 3 years might be that expensive purchase that pays off for you.
That doesn't make it worthless to figure the approximate cost per time used of a couple of different beds, maybe even a nice one.