On the contrary, maps are (IMO) one domain where FOSS is genuinely better. OpenStreetMap data is far more detailed than any corporate map, and the available clients (Osmand in particular) are far more powerful.
You-know-who can only compete because of its (admittedly useful) data on businesses. And, alas, because of ignorance among normies, many of whom are still clueless that, for example, for hiking or outdoor wayfinding, there are much better alternatives available.
Some anecdata I can offer: since last year I have used exclusively Osmand for navigating over 3000 km of cycle touring, on roads and paths of all types. The most common problem that arises is wrongly tagged surfaces (and occasionally access rights) for tracks and paths, i.e. for "roads" that do not even appear on the corporate maps. There is no comparison in terms of detail. Obviously this is less relevant for regular car drivers.
And certainly the situation for FOSS public-transit navigation is still quite poor.
https://transitous.org/ (https://github.com/public-transport/transitous) works quite well.