I guess I'd get into it if it was Rent-To-NFR. Like, you rent for a while, and at some point you can keep it without paying further installments. But you can't sell it. This would be a bargain I'd be happy to buy into since u-he's user base has grown to an age and size where license transfers are daily business.
Let's revisit where software rental plans come from. A lot of expensive software such as Adobe stuff, scientific software, CAD software reached saturated markets. It would be beyond this post to explain how it got there, and how the internet and stuff dragged this out until 200X. First, products got bundled to palm off software to people even if they don't need it. Then, those bundles themselves imposed horrenduous update costs. Then, those update costs were spread out into monthly installments, when the transition from software ownership to software rental was complete.
I'm sure someone has written books about this, but it seems obvious to me. As long as companies can grow their user base, they're good to sell individual products. The result is fast growth in number of users, with few product licenses each. That's where u-he still is (our users own own about 2 products on average, a majority owns 1). But once the user base reaches a critical point, it makes sense for companies to "sell more" to existing customers. So, Adobe back then, turn products into "suites", and make existing customers an attractive offer to go there. Once the user base has been converted into "everyone has everything", a company has reached the end of selling as its core business model. It needs to start monetizing already sold licenses. From this point on, they need to enforce paid upgrades onto the customer base. That's rental.
Obviously, this is only for companies which have more than one product. Companies with only one product can bypass the bundle phase, unless they start vertical growth (tap into other businesses, such as content creation or a more diverse product range).
This, in my observation, is where software rental comes from. It's a consequence of unsustainable growth. It's a way to make money from existing users when the user base can not be expanded any further. But we are very far away from that point, our headaches lie elsewhere.
Another question is, are there disadvantages of outsourcing the rental? Will Splice etc. try to bind customers to themselves instead of the brands they rent out? Do companies like Splice and Gobbler try to establish ecosystems in which they gather control over the user base and brands become a commodity?