For roads though they generally hook into official sources (e.g. Ordnance Survey in the UK) so they are guaranteed to get updated when the layout changes. That's not true for OSM. (Though obviously in the UK there are enough map nerds that it's very unlikely to be an issue.)

Official sources also may have outdated maps.

Especially when for example bridge was destroyed hours/days ago.

I don't know for UK, but in Swiss Alps the data is extremely scarce, which paths outright missing and Maps showing paths that can be closed or extremely dangerous.

Apple and Google are not guaranteed to be updated when government road data changes. They do their best and they have tons of money and user-reported data (like live GPS traces from users' devices) to do decent work, but there are many times that OSM map nerds do a better job. The real issue with OSM is in remote areas where not a lot of people are around on the ground to realize that it's broken or care: the first user in an area often has some volunteer work to do. But fortunately it's easy and you can do it. Any random person can make a better map of their area than Google, instead of having to beg them for it.

Can't trust Apple/Google, can't trust OSM, can't trust paper maps...

What's the right answer here?

Be aware that all maps be untrustworthy. Be aware of your environment. Don't blindly follow instructions. Have a backup plan.

Trust but verify

To use a cliche, the map is not the territory.

It highly depends on what you're doing (a road trip vs a grocery run vs hiking mountainous back country) but the first step is to do a sanity check of the route. It's very easy for many GPS apps to route people to the center of an airport for example (i.e. the middle of the runway) instead of the main terminal, and only recently have a few apps managed to do better about that. Other times you can just easily spot that it's not a great route by reviewing it for ten seconds.

> What's the right answer here?

Essentially, check before hand and if possible, use maps fit for purpose.

(E.g. Switzerland has nice public topo maps which are usually more accurate than Maps/OSM. They're available in SwissTopo app. The dedicated app also tends to show closed routes more accurately.)

And double check with local info boards about current state (many regions have websites or dedicated meterological organizations that will post recommendations and closed routes).

> What's the right answer here?

Do not ignore reality.

Do not drive around signs announcing that bridge is closed, for an example.