FWIW this is happening again in the UK right now with FTTH deployments. There are about 10-20 companies of fairly sizeable scale, with hundreds of millions of billons of GBP of funding laying fibre.

I think this is a good thing for the country (it has forced Openreach & Virgin Media to massively accelerate their FTTP plans); but it is going to be cataclysmic for the investors.

Firstly, the build cost is astronomical and completely inefficient, apparently £1000/home is pretty standard, which is 3-10x what openreach and VM are paying (these altnets have access to all the openreach ducting and poles), due to very poor efficiencies in their build process and massively overpaying for materials and labour.

Secondly, they overbuilding like crazy. I had 5 different FTTH providers at my old London apartment available, with totally separate infrastructure. This is meaning takeup is a fraction of what they expected it to be, as for the most part they expected to have at most one competitor at a property.

Third, they seem to have absolutely no idea how to market and acquire customers, since their main skill seems to be how to pitch infrastructure funds to get capital. Their rollout is very patchy nationwide or even a local area so marketing campaigns are hard to do.

There is going to be a huge wave of consolidation (at best) or bankruptcy in the sector as interest rates have risen and the calculus has totally changed.