That's like telling someone that for the price of a new BMW S1000RR motorcycle, they can instead buy a really good Honda Civic, because a Honda Civic can carry more passengers, you can sleep in it, it is more reliable, safer, cheaper to service, holds resale value better, more versatile when it comes to different weather conditions, etc. You are missing the point that those in the market for BMW S1000RR are often aware of all those factual advantages that a Honda Civic has, they just prioritize different factors in their choices than you might. Someone who is looking to buy a motorcycle isn't gonna suddenly be swayed by looking into all the factual advantages a Honda Civic can provide over a motorcycle.

Despite both items serving fundamentally the same base purpose (getting from point A to point B for cars/motorcycles; making music for OP-1/your list), and one of them is cheaper overall and on paper has a lot of factual advantages, they might simply prioritize different things and both be extremely good at different things they prioritize. I, personally, love the workflow of the original OP-1 way more than almost the exact list you produced (because it used to be pretty much my setup, except I used a different midi controller).