My bet is, no matter what the map updates will stop coming a lot sooner than the 5 years included.
The current 2.gen cars are soon to be replaced with a new model and if there is one thing Chinese manufacturers are not good at, its making sure that the "legacy" stuff they make, gets updates.
The latest map update for the 2.gen ZS EV is from November 2023, so right now the latest map update is already 1 year and 3 months old and there is no indication that the maps are about to get an update.
The maps are made by some external company i bet, so MG has to pay them to do a new updates map package, when they stop selling the 2.gen ZS EV, they get zero revenue from it, so what's their incentive to keep updating it, it will only cost them money.
And just to be a bit fair in about 2019 Vauxhall replaced their Navi 900 in their Astra series with a new infotainment / navi, people here at least were asked to pay an amount equivalent to about £2500 for a package that included that.
Updates were priced at about £100 but when they upgraded to the new system they just dropped even offering the map updates for the navi 900 cars, so some people paid £2500 extra to have satnav in their car, only to have it delivered with the latest version to be released.....How is that for poor service. (PS. I sold my car at about a year after, there is a small chance they changed their mind, but people were told by Vauxhall dealers at that time, that they would not be getting any updates, even if they wanted to buy it).