Slide film is very marginal right now, there being virtually no market at all. This point is missed by almost everyone.
Kodak once made (may still for all I know) the most archival DVD/CD ever made, but it sold poorly due to cost. Everyone things that the penny CDs and DVDs are ok, even Hollywood I guess. So, the market keeps moving in that direction.
IIRC, Kodak has a machine or two here in Rochester still in reserve that they could crank up to scale up or down in production, but for Ilford to move to color on an economical basis would require slide or curtain coating knowledge, it would need dryer capacity, it would need a line of dispersators, and it would need a lot of other ancillary equipment to move into modern color. There has to be a market to sustain the initial development costs and it just is not there. Go ahead and spin pipe dreams but you have to have a few million $$ to start up a color line.