A spreadsheet gives you a DB, a quickly and easily customized UI, and iterative / easy-to-debug data processing all in a package that everyone in the working world already understands. AND with a freedom that allows the creator to do it however they want. AND it's fairly portable.
You can build incredible things in spreadsheets. I remain convinced that it's the most creative and powerful piece of software we have available, especially so for people who can't code.
With that power and freedom comes downsides, sure; and we can debate the merits of it being online, or whether this or that vendor is preferable; but my deep appreciation for spreadsheets remains undiminished by these mere trifles.
It's the best authoring tool we've ever devised.
EDIT TO ADD: the only other thing that seems to 'rhyme' with spreadsheets in the same way is: HyperCard. Flexible workbench that let you stitch together applications, data, UX, etc. RIP HyperCard, may you be never forgotten.