Author here. What I'm seeing in particular is CRM/ERP solutions at risk. I know of two people in my peer group who are actively trying to replace a 'niche' ERP/CRM (not salesforce) with a agent built alternative. These are both >$100k/yr contracts.

They've outgrown the current (industry specific) products, arguably a long time ago. The discussions started like this:

1) Started building custom dashboards on top of data exports of said product with various AI tooling. 2) This was extremely successful, as a non developer "business" person could specify, build and iterate on the exact analytics. Painful to work with a developer on this as you need to quickly iterate once you see the data and realise where your thinking was wrong. Non developers also really struggle to explain this in a way that makes sense from a developers PoV. 3) ERP system at play wanted a renewal price which was a big increase, and API deprecation. This would require a lot of existing (pre "AI") integrations to be rewrote/redone. 4) Now building an internal replacement. They would not have even considered this before AI Agents.

FWIW this tool is not super complex, but it is extremely expensive (for what it does). It already has a load of limitations which are being worked round with various levels of horrible hacks.

There are a _lot_ of these kind of SaaS products about, for each industry. You never really hear about them.

Btw I use claude code nearly every day for many hours. Opus 4.5 has been a huge leap forward, I am blown away with how it can do 10-30 minute sessions without going wrong (Sonnet definitely needed constant babysitting). And the models/agent harnesses are only getting better. Claude Code isn't even a year old yet!