Parsoid-based read views are on the horizon. 2021 will probably start seeing small beginnings and by the end of the year, the Parsing Team expects to have made significant progress towards shifting wikis to use Parsoid HTML for read views.
There will be several milestones along the way. T265943: Decide on EOFY (June 2021) Parsoid read-view target use-case might look at mediawiki.org and/or officewiki as the first guinea pig.
Given this, MobileFrontend should start preparing to consume Parsoid HTML. There will be a transitional period (likely on the order of many months) when both Parsoid and core parser will be serving wikis as we iron out kinks in rendering, performance, features, etc. But, the final switch will likely definitely happen in 2022.
The Parsing Team's hunch is that MobileFrontend code will potentially be simplified with the switch to Parsoid HTML. For example, Parsoid output comes with section tags that are compatible with core parser output and MobileFrontend can simply consume them instead of craft these sections internally.
We are happy to collaborate with other developers to ensure that this transition can happen as smoothly as possible including addressing any missing functionality.