No, enterprise grade means they have a sales team that can take people out to lunch, and find round about ways to give kickbacks to decision makers. Being kludgy and outmoded is a common side effect, but not a requirement.
I think enterprise grade means, among other things, having the means to scale support to meet demands. A large enterprise runs databases in 100s or even 1000s of different applications, developed by maybe 100 different teams. It helps to know that the vendor is able to meet support needs, not just for the use by one team where you know the circumstances, but generally, even when you don't know them.
Isn't that what people mean when they say 'enterprise grade'?