Cloning any random piece of SaaS is something that could already be done before agentic coding, and the economics of it haven't changed meaningfully. Before, writing the clone would cost 0.5-1% of the valuation of the legacy SaaS company. Now it might be 0.1%. It doesn't make a difference -- if you can pull it off profitably today you could also have done it profitably in the past. The code is a very small part of the process of making such a clone successful, and the reason legacy software has often bad UX is not because code was expensive to write.

Circa 2012 you had a lot of devs "cloning Twitter" as a weekend project. Reproducing the UI and features of any app was never difficult and was never particularly valuable.

Last I checked, Twitter is still around, despite having been cloned 10,000 times before. And IMO most legacy SaaS has even greater stickiness than a social network (which does have tremendous stickiness)

Google uses Workday. Huge contract. You think Google, the software company most prone to rolling out internal tools for any random employee task, couldn't make its own Workday for all these years because the *code* was too expensive to write? It would have been 1 week for 1 Google dev top