There’s always a gradual refarming of the spectrum into the next G. Usually the most penetrating frequencies (ie lowest) are kept on the lower G to maximize legacy support.

For a while I had my phone stick to 3G, which doesn’t support emergency alerts, because my jurisdiction kept sending them out for joint custody disputes at 3AM 1000km away. It was fine But the 3G became unbearable and they tightened up the alert criteria.

The difference between 4G and (non-SA) 5G is fairly small compared to earlier generations. They use the same core network, and it’s actually quite possible to be connected to 4G and still see the 5G logo.

These tricks are less common in Germany though, as far as I’ve seen, so seeing 5G can serve as a weak proxy for “the carrier has at least touched this base station in the last few years”, which increases the chance they’ve upgraded its spectrum or backhaul a little bit.

Really depends on the concrete situation, though. Having a small 4G cell with 20 MHz of spectrum to yourself beats an overloaded large 5 MHz rural 5G site any day.

I’d you have a 5G phone and plan but see 4G, that usually means you are at the very edge of coverage. Thats not the experience 4G was or still is if you are in a well covered area (which would have 5G available as well)

Interesting; in Australia I'm using exclusively 4G with no problems