You're correct in that nearly all hardware now is 64bit, but the problem here isn't the hardware, it's operating systems, and more specifically, software. While most of the install-base for OSes are also 64bit these days, quite many are still 32bit, and even the 64bit OSes have to be able to run software in the wild, of which very many are still fully 32bit, and by that token, if they use libraries, it has to also be 32bit libraries. Why are there still 32bit software around?, I hear you ask. Well there are different reasons for different 32bit software ranging anywhere from "couldn't be bothered" to "An enormous codebase that will take years to refactor" or just "using old outdated software that is no longer supported but it still does the job, so why not?". On Linux we are used to compiling stuff ourselves, but for most of the World, software comes pre-compiled, certainly 90+% of Windows or Apple user installed software and even these days on Linux it's more common for basic users to install from pre-compiled binaries. If you doubt me, just see the ruckus caused when Ubuntu tried to drop 32-bit support. I am betting that any major OS that wants to remain a major OS will keep supporting 32bit software for many years to come, meaning people will keep using 32bit software and need 32bit libraries (such as sqlite3). That's why it's still available.