[thinknot]

Fibre is a very recent development... and there are a few kinds of it. Like, GPON, EPON, etc.

Before we had coax cable which required updates very often (DOCSIS versions) which usually required changing lots of equipment (not termination equipment/CPEs).

Before we had DSL which also saw lots of improvements over the years. (ADSL, ADSL2, ADSL2+, annexes, etc).

Also all these technologies require an uplink which needs to be updated from time to time.

These updates are very expensive, you can't imagine how much. A comparison with tap water is moot because, well, you don't need new, thicker pipes every 10 years.