I don't know anyone on FTTP who has contention issues.
It's far more likely to suffer contention issues than FTTC with the higher bandwidths at play
The average user uses nowhere near 5TB a month.
If that limit is an issue for your usage then that's fine. AAISP likely don't want you as a customer if you use that much data. It can be very detrimental to others.
How often does FTTP go down, really?
Mine has twice in the 1st couple months I had it.
More than my FTTC did in the previous 5 years.
ELF's (early life faults/failures) are on the increase.
Entire PON's go down everyday
They won’t be able to provide more tools for troubleshooting
Of course they do. They have 24/7 line monitoring that sends a PPP LCP echo to every single customer, every single second, showing latency, throughput, sync and packet loss on a second by second basis.
they won’t be able to provide faster response times for repairs.
They absolutely do, even on FTTP.
Their offerings don't attract you, that's fair enough.
Perhaps you don't need any of the technical features they offer and uptime/failover isn't critical to your business/work.
Those are important to other people.
There are just as many AAISP customers who wouldn't take an unlimited Talktalk connection for free. They couldn't imagine using a dynamic IPV4, no IPV6, no UK phone support, no failover to mobile data.
It's a competitive market. You're free to choose whatever provider you like.