Your drive block and brake/ basket drive tube are worn out. The silver tube that is beneath that plastic piece should have squared cornered tabs sticking up that engage a block that supports the basket. They engage the drive block. Notice the worn off corners...it probably made a thunking noise went it stopped spinning for a while and then the lip of the block wore away until the block just slid down.

If you've changed the clutch you can do the basket drive too, it's just above it and not hard to do, but more complex. You'd need to pull basket out first, which may not be easy at this point. The drive block fits into the tapered part of the basket. You'll need a special spanner to pull that main nut off, it's the one with the 4 notches. If you can get the nut off and the basket out a mallet will drive the drive block upward off the tube.

If all that happens without drama, then you pull trans and clutch as before and pull the drive tube out from the bottom.

Realistically, unless you love this machine you can find a used direct drive similar to it for $100 on craigslist and save yourself a ton of work. It would take me about 90 minutes to do this work if all went well. You'll probably spend most of an afternoon.

Parts if you really want to do it, not including spanner wrench.

Whirlpool WP389140 Washer Drive Block - AppliancePartsPros.com

Whirlpool W10820043 Basktdrive - AppliancePartsPros.com

If you're a DIY guy it's totally possible to do, just is it worth doing?

I'd fix before buying new... new ones are miserable, poorly made, and prone to early failures. If you get 5 years out of it you've been lucky.

I'll take a 10 yr old direct drive like yours over anything made today, other than maybe Speedqueen models; which are basically old designs still.

I tell customers that routinely. I have a 15yr old version of that one you have. They lasted for 20yrs frequently. I see them from the 90's pretty often. They aren't energy or water efficient but easier on the wallet than a new one.