However, it is different from the internet bubble partially for the reason you describe.
There have been a few IPOs, but they perhaps happened earlier in the cycle, or companies are pivoting into AI. I'm thinking companies like Palantir, which was always AI, or Salesforce which is making a big AI pivot.
Most of the funding is not coming from public sectors. There is so much private capital available that it isn't necessary. I believe the bubble is in VC, which some would think is find because it protects public markets from the crash, but I'm not sure that is correct.
When the VC money stops flowing into AI, I think it will send a shockwave through the public markets. The huge valuations of companies like OpenAI, Anthropic, etc will be repriced, which will probably force a re-pricing of public darlings like Palantir, Microsoft, NVIDIA.
If VC funds aren't buying NVIDIA chips and building data centers, everyone will feel the need to re-price.
It's emotional, not logical.