Doubt they’d remove Jon from continuity; DC relies on comics to develop new IPs, and family Supes is the mainstream depiction right now. Not to mention they might have an eye on the new 5G gen (Jon Superman, Jace Batman, Yara Wonder Woman, Jo Green Lantern, Andy Aquawoman) for adaptations if they ever manage to reach their Phase 4. If Jon’s solo fails he can still be connected with his gen, and DC can just move him to the sidelines and keep their options open for other projects. Plus there are plenty of Jon-less Superman books already.
I do expect at some point for Jon to die because everyone does in comics for drama purposes, but they always get brought back.