I would not be surprised if Tokyo Monorail adopts the same policy as JR East. Besides, given the choice between PASMO and Tokyo Monorail SUICA, I would opt for PASMO because Tokyo Monorail SUICA can only be refunded at Tokyo Monorail stations.

As AlwaysAisle mentioned, Welcome SUICA will still be sold. I understand that these have a predetermined expiry date and no deposit required. Seems like a shame to continue selling the disposable cards while limiting access to the returnable / recyclable ones but I guess it makes sense.

I would like to see a "SUICA amnesty" to get people to return the SUICA that they have lying around at home, but perhaps it's not cost effective to salvage chips from old cards.