Good thing from the current situation is it being the end of times for these services. Constant need for income increase to appease share holders means infinite growth, which is impossible. But individual doesn't see that, they just want more. So progress of any software towards service model is pretty straight forward.

First they start splitting software into smaller versions and selling both for slightly higher price combined than when they were single piece. Then they start releasing more frequent versions but that has limited impact. So they start introducing forward incompatibilities. Only new software will support both old and new versions of the document, forcing buyers to buy latest. When that reaches its optimal maximum they decide to switch to yearly subscription and force everyone to use those by same ways as they forced them to use newer versions.

Subscription based model is limited. It has no progression other than increase in price and it's only a matter of testing how much people are willing to pay. Sometimes even go above reasonable price but then go with "exclusive" content as if to justify higher price. This of course works for a while, but exclusive content costs money and is harder to produce consistently at high quality...

And after that, there's no progression. It's a battle royale among service provides but they can't back out because of share holders and can't revert to other business models. So some of them will stretch themselves thin and burst others will keep on living from that vapor until a new contender comes.