Canonical can collaborate with teams from Debian, Linux Mint and System76 to create a unified 32-bit repository to be included on all of their systems and boom job done. The burden of maintaining the 32-bit libraries would be shifted across the entire mainstream Ubuntu derivative stack and Canonical would have less of an issue maintaining access to 32-bit libs.
I think S76 with Pop!_OS could take this as an opportunity to provide to end users a 32-bit "Ubuntu". It would fill a unique niche of the market (People from Ubuntu wanting 32-bit libraries hosted by the distributor) in a world where there isn't 32-bit Ubuntu.