I am still using Faiphone 1 (I was one of the first 500) for phone calls and the old S3 Neo of my son for apps. Now next year all carrier will shut down 3G, thus forcing me to a new phone at least for data.
As you can see I am a real long term user.
Therefore I will buy a Fairphone 3+ only if it is guaranteed that the day a 5G support by Fairphone is possible, I will only need to change the sending/receiving module.
I don’t want to be forced again to a new phone the day every carrier will shut down 4G.