Whether it is future proof or not is up to the manufacturers of the product and the requirements of macOS's to come.
If you buy a scanner that definitely works with Catalina, then it will work with Catalina for as long as the scanner or
the mac works. But if you decide to upgrade your macs operating system then it is up to the scanners manufacturers to
update the drivers so it will continue to function in the newer OS's.
Having said that the manufacturer is under no obligation to keep providing drivers for a particular model of scanner or
other hardware forever, they are in the business of selling products so they eventually obsolete their product so they can
see newer hardware..