Except the purpose of the section is to say that R&E has to be amortized. So it seems pretty clear to me that software development costs have to be amortized.

Exactly. I don't see how anyone can read this and tell the IRS with a straight face that their software dev doesn't need to be ammortized.

According to Bloomberg [1], for ongoing business expenses, it doesn’t. For startup costs, it does need to if you want these RD credits.

[1] https://news.bloombergtax.com/tax-insights-and-commentary/ch...

It is ambiguous even if you disagree with Bloomberg.

Not one mention of "software" in that article. It's clearly written in a general context where this may be true. They don't mention c(3) at all:

"For purposes of this section, any amount paid or incurred in connection with the development of any software shall be treated as a research or experimental expenditure."