Genuinely curious whether there were films you found on the DVD service that were inaccessible via your local library loan system (if you are in the US that is, did Netflix ever do the DVD service outside the US though?)
Good library systems have a good percentage of DVD released films readily available for free.
I'm in a fairly rural area. Our library system doesn't have much. However, just across the county line is a much more populated county with a lot more ... of everything in their library system. Turns out I can 'join' their library for $25/year. It's somewhat more convenient, because it's about an 8 minute walk from my office, and open more. The local one to my home has cut back hours. I'd like to find a way to 'support' my local library system more, but short of donating tens of thousands to them on my own, there's not much I can do. I've started to use them some more (which may help activity numbers for future budgets) but the $25/year access nets me probably 10x as much stuff.
I had a Netflix DVD subscription for years, but cancelled it more than a decade ago. I found even then that most of the obscure / out of print / hard to find DVDs were simply being stolen by the people who rented them and it would just sit on your queue forever. Since these were out of print they could not be replaced and eventually would be removed from their catalog.
There are of course many movies on DVD that have not been released on streaming or Blu-Ray, I suppose the size of your local library system could make a big difference on what is available. Especially if you live in a more rural or remote area.
There has only been one film I've been unable to find in our library system. It's an out of print foreign film and impossible to buy new or stream so I periodically would check eBay. Finally I found a copy at a good price and bought it.
The seller sent me a DVD-R in a case with an inkjet printed cover. I went out of my way not to pirate it and ended up doing so anyway. :(
In general though, our library has completely replaced Netflix for our house for ages. It's great.
Yes the films are available through my local public library system, and yes they are "free" to borrow. However it is neither convenient nor reliable to borrow a film from my library. Would I pay the library $10/month to be as convenient and available as Netflix was? Yes.
Good library systems have a good percentage of DVD released films readily available for free.