The only over-builds I saw were primarily done for making a "dog and pony show" to investors and prospective customers. By over-build I mean a lot of data-center space was built out, many of the data-centers built out large highly redundant ATS/UPS with numerous generators and fuel tanks. Some data-centers had redundant commercial power coming in from 2 to 3 sub-stations when feasible and multiple egress to local telco and many redundant circuits that by todays standards would be very low bandwidth.

Most of this was for show and caused many companies to file chapter 11 several times, change names several times, merge with several companies several times and so on. Over time circuits got faster, servers got faster and used less power. That's about it. Many of those build-outs are still around, just different butts in chairs and far fewer of them.

I don't know what the parallels will be compared to today because I don't know the ultimate goals for government, military and civilian use of AI {AGI}?. You may enjoy listening to this podcast [1] for some idea of why people are scrambling and why it's probably premature to even guess where all of this will land.

[1] - https://www.youtube.com/watch?v=NufB1LL_rCU [video][2 hours 7 mins]