Generally, glycol with silicate was bad for journal bearings - before lead-free bearings were introduced all rod/main bearings were made with a Babbitt overlay on steel shells. Coolant will wipe out the overlay.There was a study by I believe Chevron about 20 years ago. They showed that propylene glycol coolant does not tear up a motor the way Ethylene glycol does when leaking into, and mixing with the oil.
Newer engines with aluminum-silicon alloy journal bearings might withstand coolant in oil situations better.