Hi,
I see what you mean, but I don't think that there is so much use for it that an option would be useful for enough people compare to the fact that there are already too many options.
Basically, from that discussion, it would only have an application when you have products with a limited quantity that you can replenish, that you don't want to display the price of the product after the sale, but that you still want to display the sold products, and that you also have free products.
On the other end, we have so much options that even though the contact feature has been there for years, and you've been using HikaShop for years, you didn't notice it.
In such rare cases, I would recommend to just add that one line of code in the listing_price view file. It's not like this view file is going to change much in the future anyway and we already have too many options so such option would just make it more confusing.
Also, note that there are several ways to make view overrides. The way you do, where you modify the code in the override file is not the best for forward compatibility. The best is actually to remove the whole code in the override and just include the original file. That way, you can add your condition at the top of the override in order to use or not the standard listing_price view file. So you get the updates to the view file and you still have that extra condition to it.