As deployed, most OpenStack SDNs will use OVS or similar software on top of a (xen,kvm) Hypervisor, connected to some kind of central controller, which just maybe would look kinda like OpenFlow. But all of this is running as an overlay on top of a much more traditional network.
This is very different than a TOR switch or core-router running OpenFlow. Only a few places are running more than a couple thousand VMs in a single SDN, and its nothing like what is being discussed above.
Sure, and OVS (especially with OVN) is pretty capable. (And we haven't even touched OVS DPDK.)
But if you need the big guns there are a ton of OpenStack Neutron plugins, OpenDaylight being one of them (networking-odl) and there are the classical/traditional vendor ones (Cisco, Arista, and so on).
I think the future is very much means this jungle of APIs integrating in whatever tangled ways, and eventually the reliable, robust and sane ones will prevail.
Also see Project Calico for containers, they use the linux kernel as FIB, but obviously they could just as well use OpenFlow to program switches for bare metal machines (which then might run containers).