It's not clear from the article if this cost figure includes software engineering cost which would be significant in Tesla's case.
Or at least that's the traditional view; purchasers of Model 3's now expect OTA updates so there is a little bit of R&D cost in the future but it's very minor compared to what's already been spent.
That also doesn't include self-driving R&D, but that's not included in the $35K base model so is also irrelevant.
Toyota spent almost $10 billion on R&D last year. Ford $8 billion. VW spent $15 billion.
Tesla spent $1.5 billion. What is it that makes people think that Tesla's R&D spend is so significant, and that it will diminish drastically in the future? This is an R&D intensive industry.
All the routine work was included in Run The Business budgeting just like tangible material purchases.
The criteria for qualification usually boiled down to 'was there an element of unknown quantity in the project?' - which left enormous room for interpretation, as basically anything that wasn't maintenance (RTB) could be justified.
We would regularly, across the firm, get $50m tax benefits a year out of this effort.
I'm not an accountant, but I'd be interested in just how rigorous the notion of 'R&D' is in a company's annual returns. It smells of PR to me.