MHI has made the occasional hint in the direction of further crj development:

https://aviationweek.com/mro/mitsubi...-spacejet-halt
”Interestingly, MHI also wants to expand its MRO reach to non-CRJ platforms, as well as pursue a feasibility study for a potential CRJ upgrade.”

With the continued evidence of backbone at UA/DL re: the 86,000lb limit, and the difficulty in getting an ejet or a spacejet under it with modern efficient engines, the crj has some potential for a 3rd act.

Plenty of discussions on a.net about how to get there. Basically,
1. easy plug and play to replace 30 y/o avionics with lighter, more reliable, cooler running more sophisticated tech.
2. Use marketing words like “atmosphere” etc. to get pax into the little tube.
3. with no suitable replacement for the 40 y/o cf34 tech, and no business case for developing a new engine in this class, its either a “leap” like evolution of the cf34, or adapt the oversize gtf. Both are much heavier, leading to a 76 seat crj 800. ie, a crj900 ahead of the wing with the shorter aft fus of the 700 behind the wing.

If the regional is to continue in anything like it’s present form it will require something like this, a 76 seater w/50 seat fuel burn, or a new turboprop.