All correct. To add, the main problem with ceramics is their fragility under tensile stresses. Spinning at high speeds puts the blades into tensile stress, which tends to "open up" microscopic defects in the crystal structure and cause complete failure.

Some researchers from the academic lab where I work have been working on a turbine configuration in which ceramic turbine blades undergo compressive, instead of tensile, stresses in rotation: https://www.exonetik.com/turbo Interesting stuff, but it's a huge challenge to bring entirely new jet engines, as TFA mentions, to certification and market.