This product seems pretty sus…
That said, I am not particularly knowledgeable about nitrate or nitric oxide etc supplementation.
I assume it is mainly an ease of use/consumption thing as you mentioned - vs. eating actual beets (Not a fan personally, as they always taste strongly of dirt to me due to the Geosmin) or drinking bottled beet juice concentrate.
A semi-related side rant -
I don’t care about the fake “natural” advertising that is so prevalent nowadays, if I want nitrates I’ll gladly add straight curing salt (that I use to cook with and make corned beef, bacon etc), instead of having a farm dope up a field with extra nitrate fertilizer, have that be taken in by the beets as they grow, then have the beets processed into some sort of extracted concentrated juice/powder.
Same sort of thing happens when they advertise products with “no added nitrate” or “uncured” and they instead add processed refined celery juice powder which has a high nitrate content.