The Dorico developers should easily be able to program it to interpret certain text indications as playing techniques. So arco and pizz. text being interpreted as techniques properly is entirely doable from a programming perspective.
The only challenge though is if the original file has something else in the same text block as the arco or pizz., for instance “unis., arco” it should split into two playing techniques, unis. and arco. What if one doesn’t exist as a playing technique? When do you fall back on system text?
Those challenges can be solved by the programmers (I have no doubt about it) but it just takes time and priority vs. other things.