Google Chrome on Android version 74.0.3729 can no longer clear history, cookies, local data, etc. See screenshot below.
Even when this process is running completely uninterrupted, nothing happens. I.e., changing display sleep time to 30 minutes, Google Chrome will not finish.
Problem solution: Shut down phone. Power up again, and try again to delete cookies. This time it worked. Seems that some Android Chrome internal locking and contention blocked deletion.