I suggest a game: anyone have some personal activities to do on a desktop like managing a bunch of files, scheduling events with a calendar or something similar and so on. Oh nothing special BUT actual widespread systems what offer?

There are plenty of "calendar app(s)", but you can only ad some entries, no file attachments, no links to relevant mail(s), ... There are plenty of file managers but almost NONE offer anything more than files and directories approach, veeeery few allow for basic tagging and search the tags, just plain text search&narrow, no booleans or something alike for most, even less offer full text search inside files content and files metadata, oh and for all, even Google Drive, mails are not files... Long story short: the actual computing model offer NO INTEGRATION and BIG fragmentation. Initially such choice was for commercial purpose: building a fully integrated environment like Xerox did was extremely complex and do not offer much profit opportunities (especially when it's hard to tell what one can do with such system) while on contrary selling simple systems with limited functionalities and selling extra functionalities a bit at a time, allow BIG profit. But as correctly stated by the Conway's law after a certain timeframe all apps try to do anything since integration is demanded and is not possible in the present model.

Since years few timid ways of integration have seen the light, MOSTLY only when someone have found a way to avoid giving much power to the end user. For instance we have seen the web 2.0 as a successor (aspiring, at least) of classic widget-based UIs and desktop environments, those have evolved to be a very complex WebVM [1] bootloaders and the web 2.0 is a kind of modern original integrated environment "document based" where anything can be linked, most parts can be integrated in a "newly composed page" and so on. Of course, in the original desktop the users do write the "active documents" or "the UI", extending the ones offered by the environment, in the web 2.0 model the user is practically powerless since writing personal JS/CSS etc to bend someone else UIs is a painful and pointless exercise, but that's is. End users programming is came back a little bit, again in limited and limiting ways with notebook UIs, "low code" environments and so on, since well... No point-and-click UIs can cover all functionalities while simple textual strings known as "code" can.

Long story short again: no, "AI" is not an alternated vision, a potential totally different future. The alternate vision is the original desktop model, of people who have a fully integrated, flexible, user-programmable, environment and can communicate with other peers between them. The future is no need of a crappy website per bank to operate but simple APIs, functions the user can call/integrate in hes/shes own documents "notes" to operate. This alternative vision of computing was from the past, still exists a little bit in the present (see https://youtu.be/B6jfrrwR10k as a simple Emacs usage demo) and is the future, the potential future, if enough people realize it.

This model do not happen mostly because those who can spread it do not want at all giving such power to anyone who want to learn. Giving it means the end of the platform goose that lays golden eggs, giving up any position/size advantage and so on, while most ignore it's existence so do not push back against alternate evolution.

The really future model, beside the above would be the integration of human brain and an artificial exobrain, so we do not need specific UIs limited by their physical IO interfaces and concept model. But as per the "AI", the much hyped "neuralink" and alike are just very expensive toys so far, we are far behind the dawn of such era.

[1] the monsters mostly known as browsers, that name remain for legacy reason ONLY