That explanation is correct but somewhat incomplete. Precision approaches with low minimums (the decision point where a missed approach must be initiated) also have an alternate source of vertical guidance (in the typical case of an ILS, it’s a radio beam bounced off the ground and up along the approach path and the pilot has a very tight indication of whether they’re below, on, or above that beam).
The radio altimeter is a secondary or tertiary source of height above terrain information, not a primary.
Without a functioning radio altimeter, some aircraft on approach to some runways would have to use higher minimums than would be available if they have a functioning unit. This will contribute to some missed approaches or diversions in low weather. (Where a missed approach almost never ends in a crash in airline operations but rather a second attempt or a diversion.)
The radio altimeter is a secondary or tertiary source of height above terrain information, not a primary.
Without a functioning radio altimeter, some aircraft on approach to some runways would have to use higher minimums than would be available if they have a functioning unit. This will contribute to some missed approaches or diversions in low weather. (Where a missed approach almost never ends in a crash in airline operations but rather a second attempt or a diversion.)