Sure, I actually have a degree in botanical sciences, majoring in Olericulture -which is the study of soft-skinned herbivorous plants for food production. So, I can speak pretty confidently on it. Strictly, a tree is a large, woody, perennial plant that grows slowly over time and produces offspring in the form of angiosperms e.g. apple tree, or gymnosperms e.g. a spruce tree -on a yearly-ish basis. The banana plants root is a rhizome, it's a specialised underground stem that grows sectionally, forming nodes. If you've ever encountered runner varieties of bamboo, you'll know what that means. They don't penetrate nearly as deeply into the soil, they can spread rapidly and herbivorous plants like the banana are much easier to clone than woody trees.

Because it is a herb and not a tree, Banana plants grow very very fast and they die after they give fruit and that is a real key point in the difference. There are no annual trees, because trees grow slowly and very hardily. Trees are perennial, meaning their above ground structure will remain alive throughout the seasons and after fruiting. If you see a crop of banana plants. They're 9 months old at fully grown. Their stems are formed by sections of leaves that grow over each other, kinda like certain varieties of bamboo, if you look at how they grow you'll see that in the stem. After the fruiting they die. Banana plants grow fast, produce offspring and they die back to the rhizome. Your commercially grown banana plant will live roughly a year. After it fruits, doesn't matter if it was 10ft tall, it will die back to the rhizome. Much in the same way ferns will. Trees don't do that. There are tress alive today that are millions of years old. There is no herb that is millions of years old. It's a completely different ecological niche. Bananas are soft skinned, grow rapidly, produce offspring, wither and die. Trees are woody, produce bark to protect themselves and live for generations, repeatedly producing offspring.

“trees” (and “herbs”) aren’t natural clades but rather form‑based, morphological grades, and only really colloquially so. In cladistic terms they’re polyphyletic or at best paraphyletic. Its a term that pulls together organisms by shared structure (woodiness, height, lack of wood) rather than by a single common ancestor and all its descendants. But it doesn’t need to meet all of those terms to fall into the group.

You don't need to specify "natural clade" a clade is a grouping of a common ancestor and all of its descendants. There is no unnatural clade. It also doesn't mean anything in terms of classifying a plant as a tree. We created that classification. That's why things don't fit neatly into everything 100% of the time. But you can say the same thing about land animals too and sea creatures and basically any category of living thing. Trees don't need to have a singular common ancestor because convergent evolution means they can develop enough shared traits which make them a discreet group of organisms. As opposed to the banana plant which lacks the morphological characteristics of a tree.

You can’t grow them like an “herb”, whatever tf that is.

That is a very dumb statement. There's lots of information you can get online bro and it's very easy to sound like you know what you're talking about. If you're talking to people who aren't familiar with the subject. If you want someone educated in the field to take your opinion seriously, don't use scientific terms like "morphology" and "polyphyletic" and then demonstrate that you don't know what an herbivorous plant is. The first thing you learn in undergrad, after the structure of flowering plants and types of meristemic tissue, is herbivorous plants.

Other things real quick, herbivorous plants have way more water and a much bigger demand for it as well. That's why Bananas are grown at the tropics and in greenhouses and why established trees can survive drought conditions year-over-year. Bananas need the humidity to be healthy and produce fruit. You can buy a banana plant and keep it in your house for years with no fruit, because it's unlikely to meet the conditions necessary. That's why this one took 4 years to fruit.

If you need more practical differentiation, that you can experience yourself. Get a little mini chain saw and cut through a limb on a tree, after that, rev up the saw and try to cut through the bottom of a fully grown Banana. Lastly, I get what you're saying. The argument is there's no such thing as a tree like there's no such thing as a fish. But the differentiation is important in terms of botany, because yeah the existence of woodies is due to convergent evolution. But, if you're a horticulturalist the tools and practices for tree care are a totally different discipline to growing and producing food through Olericulture. Which is what banana cultivation would fall under.

Sources: Bsc Botanical Science and Practices, 2 years as director of a hydroponics facility, 1 year as a climbing arborist's assistant.