It could be a clutch problem. If it was the coupler, you wouldn't get any agitating action either. See what the shaft is doing when in spin mode. If it's not spinning, most likely it's a clutch. Not an expensive repair.

I replaced the clutch thinking that was the problem....no joy. Can I assume the transmission is okay since the clutch was spinning?

If the clutch drum (shiny chrome disc atop the tranmission) turns during spin, then the problem is not inside the transmission. If it doesn't spin then all, or at least part, of the problem is inside the tranny.

Is the lid switch accessible to trigger it manually with the lid open? If so, set the machine to spin, press the lid switch to get it going, and manually turn the basket clockwise. Does that help the spin get going? The spin brake may not be releasing if you can't turn the basket or it's very difficult to turn.

This link is a service manual for direct-drive washers at Whirlpool's tech site.
L-55

You're the man, brother. Pulled the pump/tranny/motor assembly out and you hit it the nail on the head. The brake was hanging up. A little cleaning and reinstall and I'm good to go. Six loads down with no problems. I had checked for what a replacement machine would be, and a new Kenmore Elite is $925. My total investment on the new clutch was $50. Can't tell you how much I appreciate your help.