I don’t think this comparison quite works. The boxed set already exists. It went out of print, but you can still buy PDFs of the books. This is a Kickstarter to meet demand for a reprint, which is also using that demand to bootstrap new products. That seems like a pretty smart business plan to me.You know, for all the complaints we are giving WotC for re-issuing the updated monster books once, as a community we sure don't care if Necrotic Gnome re-releases the same stuff every year.
My poor wallet though. I don’t even run OSE, but I love the adventures and stuff they put out. I just finished running Halls of the Blood King, and it was awesome.