Recent behind the scenes changes suggest this may be a possibility.
Assassin's Creed Valhalla screenshot

In 2019, the final Ubisoft game on Steam was released. That game was Trials Rising. Since then, if you were a PC owner and a fan of Ubisoft's output, you were only able to purchase their titles from their first-party Ubisoft Connect or through everyone's favorite storefront, the Epic Games Store. As the months turned to years, it seemed like Ubisoft's return to Steam just wasn't going to happen.

This week, a few new discoveries were made that could indicate Ubisoft is at least strongly considering a return to Steam.

The YoobieRE Github group, which are currently working on a SteamDB equivalent for Ubisoft Connect, noticed a few fresh references to Steam versions of games. This is noteworthy because the games they discovered "Steam" on include Assassin's Creed Valhalla and Roller Champions, two titles that came out after Ubisoft parted ways from Valve's digital platform.

Specifically, the references found are labeled as "Assassin's Creed Valhalla [STEAM]" and "Roller Champions Steam." These were found under the label of "Internal Dev/QC."

Back in 2021, SteamDB itself noted that a version of Ubisoft Connect appeared on the Steam database. Though at the time, it was largely assumed to be added for the older Ubisoft titles that were released on Steam prior to the split.

The general idea here is that Ubisoft may be testing a way to have their games return to Steam while also utilizing their Ubisoft Connect client. Think of how EA titles on Steam launch the Origin client (or the EA app if you updated) and you might have something similar here with Ubisoft Connect. Over on the Epic's client, Ubisoft Connect is used when launching a game through the Epic Games Launcher. Rainbow Six Siege on Steam also makes heavy use of an Ubisoft account and their client already.

Ubisoft returning to Steam may not be too surprising when you look at other studios that decided to leave Steam in the past. As mentioned, EA left Steam for a while before returning. Microsoft also did the same thing and they have since returned and in a very big way at that. Activision also left Steam for several years, only to return this year with releases such as Spyro Reignited Trilogy, Crash Bandicoot 4, and Call of Duty: Modern Warfare 2. The last of which is busy celebrating its biggest franchise launch ever this week.

Naturally, all of these discoveries and anecdotes aren't confirmation of anything. While it would be nice to see a major publisher return to Steam, it's best to keep expectations in check until an official announcement is made, if it ever is.