Throughout my many years as a Pagan, I've floated between a lot of different paths, including different ways of seeing the Gods. When I considered myself Wiccan, I held a typical gendered-duotheist viewpoint, in which all Gods were ultimately One God, and all Goddesses were ultimately One Goddess. I eventually came to the opinion that this was "fluffy"—it really isn't—and declared I was a hard polytheist for a while, in which all Gods are completely separate, distinct individuals. When I became Kemetic Orthodox, we viewed all the Gods as Names of Netjer, so we related to them both as individuals and as an overarching singular God.
So, what's my opinion now? Well, for the most part, I don't concern myself with it too much. I worship the Gods as if they are separate individuals with great power I, as a human, can't fully comprehend, and because of this, I generally think that most ways of seeing the Gods will at least get you where you need to be, even if it's not literally how things work (I still think gendered duotheism is borderline offensive, though).
If the reality is some sort of soft polytheism—in which all of the Gods are ultimately one or a few Gods—they came to us under individual names with different personalities and cultures for a reason. Ancient Romans were really big on, when they encountered a God from a different culture, finding comparisons between that God and one of their own and declaring they are actually the same God. While I don't personally relate to the Gods that way, it wouldn't be that weird if it were the case. Humans are incredibly context-dependent, and we are often multi-cultural ourselves, doing things differently and sometimes taking on different personalities depending on where we are and who we are talking to. In the Pagan community, I am "Wolfpeach." At work, I am "Jackson." Among certain friends, I am "Jack." I might even still be called "Setkheni-itw" among Kemetic folks. I behave differently in all these contexts, I dress differently, I speak differently. And while I'm ultimately the same person, people who meet me outside of the original context they met me in may be shocked at the kind of person they encounter. Once, I was at a queer event at which I unexpectedly bumped into a coworker. She was shocked to find my nametag said "Jack," that I was wearing enormous pincher earrings instead of my more work-friendly plugs, and learned I am trans and had this whole "female" history from years before we'd met.
In the same way, it's not unreasonable to expect that Gods—who have powers humans don't necessarily understand—could appear to different cultures in ways that seem different enough that one might think they are conclusively separate Gods. Even things like differing taboos can easily be contextual. I like raw onions on tacos, but not on burgers. If somebody constantly saw me order burgers without raw onions, and never saw me order tacos, they might think I don't like raw onions at all. I won't drink water at my parents' house or straight from my own tap because I think that water tastes bad, but I'll drink water at a restaurant, or that I ran through a Brita filter.
So... what about the other way around? What if people are assuming that multiple Gods are the same God when they really aren't? While this risk is why I generally interact with Gods as individuals, I don't think the risk of problems from this is that high, especially when you are talking about Gods with very similar roles. Let's say you have decided that Artemis, Diana, Skaði, Mielikki, Pakhet, Dali, and Devana are all just names of the same Goddess.
Let's also say that this is actually incorrect, and that they actually are all separate individuals.
How much of a problem would this be, really? If you're calling them something super generic—say, "The Goddess of the Hunt"—then that's more of a title than a name, and that title applies to all of them. It's an imperfect example, but I have like three doctors I regularly go to, and when talking about them to others I just call all of them "the doctor." If I go to one of my doctors' clinics and say "I have an appointment with the doctor," we all know who I'm talking about.
This is not to say I think the Gods in this scenario are dumb and unaware that people are seeing them as different Gods.
Happy Trails,
Wolfpeach