My assumption is, if tax folks in the US were looking Jealously at US companies with large Multinational presence declaring a lot of their profits abroad. They might have noticed that some of them have large dev presence in US, but through complex accounting, IP transfers, licensing and other actions are able to claim that majority of the value is generated outside of the US.
If a company had, say, 100k software devs, 50k in the US, and 50k scattered across other countries, but claimed the value of it's software was primarily in Puerto Rico and Ireland... In that case, I'd expect questions around the 50k devs in the US.
Is software dev the only activity where this is possible - no, but is currently by the far the largest and the largest growth industry.