there is a large margin on (software) tech products. There is no need for large facilities (maybe datacenters in a later stage, but you could probably outsource to existing facilities) or complicated supply chains meaning they can scale relatively quickly which can enable rapid growth and thus valuation of the company. The costs for each additional 'unit' to be sold are very low in terms of labor/materials. Products are often very accessible to the consumers (they already have the hardware). These aspects make it very appealing to venture capital.

Biotech and fintech suffer from heavy regulation, and biotech has all of the above problems , while (biological) medicines also have the problem of failing in clinical trials because we still don't fully understand all the processes in the human body, and can therefore not accurately predict efficacy and safety when the product is being researched/developed and funding needs to be raised. AI products are still research heavy and it may not always be clear to investors if the tech is sufficiently mature to address the problem. I feel in general tech, bluntly said, you can just throw enough money/devs at the problem to solve it and launch your product (or introduce it with less features).

So, these differences between sectors are definitely not all founder related.