It is not difficult to verify whether a name is current. For hybrids you enter the grex name in one of the databases (such as the RHS), and it returns all genera where the grex name is used. It is usually obvious which one is currently correct.

For species you can use Kew or Orchidroots. Same process.

Shouldn't DNA analysis lead to the final answer and the end of splitting/lumping?

The RHS database has gotten better. a lot more forgiving recently. And Orchidroots lists hybrids as well as species, is pretty up-to-date.

No. A person or panel must decide what DNA patterns represent significant differences. There will always be disagreement and reclassification.

Also, DNA shows relationships (what is more closely related to what) But the decision as to where to draw the "genus lines" is a human decision. Nature doesn't care, sometimes is messy.

Maybe I'm lacking respect for tradition, but I find the problem is born out of its adherence. If we don't restrict ourselves to genus and species, we could have multiple levels of categories and subcategories that capture any level of similarity. In that case, it would be, for example, both correct to call a plant Laelia purpurata and Cattleya purpurata, or perhaps Cattleya sub. Laelia purpurata, or whatever the nomenclature is decided to be. Of course a "genus" could still exist for taxonomists, but there's no reason anyone else e.g. hobbyists should use such a formality instead of another categorization that provides more data. It is useful to know that Laelias can breed with other Cattleyas, and it is also useful to know that Laelias have characteristics that distinguish them from other Cattleyas. Both the lumping and splitting have merit if only we could get over the idea that everything has to fit into that box.

I'd be curious to know the average age of all the commenters on this thread, given the resistance to science and making it seem like finding cultural info was ever about the genus when it should always be about the species.

I'm an old poop... probably one of the oldest of the commenters on the Board (not going to give a number though) I accept the science - knowing that it's not cast in concrete. Science gets refined and therefore there is no reason to believe that there will be no more changes. While I agree that one generally needs to get down to the species level to really make any sense about culture, there are some situations where one can "know something" about a plant at the genus level, and lumping does detract. Example... when I buy a Sophronitis, I have a pretty good idea of the culture for most of the species within that grouping. Calling them Cattleya not so much. Then I DO need to get to the species level to make any sense of the culture (or for that matter, whether I have room for it in my yard.) A Phalaenopsis in the traditional sense is another one... There are some small variations on the cultural theme, but in general, say "Phalaenopsis" and one has a pretty good idea how to take care of it, even if it is NOID grocery store hybrid. Throw Hygrochilus parishii (Phal. hygrochilus) and Sedirea jaonica (Phal. japonica) into the mix, totally different,. Of course, changing tags on thousands of plants in a collection isn't going to happen, keeps the mind young maintaining a mental cross reference. Which is not a reason to not follow the science, but does cause some angst.

So why not take it further, using your example as a reference? Phalaenopsis also had Doritis lumped into it, and the care is quite different . . . or how about things that have been Phalaenopsis for a while, like the different sections within the genus (Polychilos and Aphllyae stand out as needing very different care).

The argument is basically moot, because the plant before you is the plant before you, regardless of the name that was given to it by humans, either 10 or 100 years ago. Hearing people him and haw about the ever-changing scientific classification feels performative and exhausting.

People who dedicate their LIVES to biology and genetic research and the institutions forking over the funding to support their knowledge and findings is what we could be talking about. Cataloging life in the dire times we live in should be one of the most important things we are all doing and celebrating.

Just keep in mind that the cataloging process is imperfect too. The decision about how much difference in the DNA makes a different species - or different genus - is a human decision. Nature doesn't care. Hybrid swarms also muddy the water. (Example, for the European Mediterranean-zone terrestrials, the taxonomy is a hot mess. Same for the Central American Sobralias. Put a name on it, and you likely still don't know what it REALLY is)