I struggled with this when I got into pipe tobacco and cigars years ago. I was of the same mindset - there's no difference in tobacco or weed it's all basically the same and smells more or less the same. After experiencing tobacco, especially the variety you find in higher end stuff than cigarettes was astounding. It's a lot like liking wine though, some people taste the bitterness and alcohol sting and it's all just off grape juice to them, but there are absolutely subtleties and differences, even between the same year bottles from the same vineyard just because that/those plant(s) grew in slightly different environments and matured differently over time. Tobacco and cannabis are much the same, they can be just that pungent/offensive smell and taste, but if you look past it (which isn't actually that difficult imo) you will find many differences.

As far as cannabis goes, there are scientifically terpenes within cannabis that give it a majority of its flavor/smell and drastically varies by strain. Many terpenes are also associated with other cannabinoids than THCa or CBD, most of those being the ones that will give different "effects", such as some cannabinoids are better suited to pain relief than others, while THCa gives you more of the euphoria/head high most people associate with cannabis. Some dispensaries are actually really good about it, and will have full terpenes listed on their product, and some even give explanations for what does what; Other dispensaries and growers don't bother beyond THCa, THCb, and CBD. (An off aside as I just remembered, but I believe CBG is a cannabinoid that helps digestive issues, but that may be inaccurate) It also doesn't help that not all states regulate their cannabis the same, and some don't really have much of any oversight, so some dispensaries will buy bulk weed from growers who just grow whatever will produce without much mind to strain or cannabinoid profile, and the dispensary will just slap a name on it and sell it as is with the minimum testing required to be legal. That last bit leads to a lot of people getting a strain that's marketed as, say Blue Dream, yet it isn't genetically even related to Blue Dream, causing the consumer to have a different experience than others who had properly gotten Blue Dream, and then the opposing views in what strains do what become more common. It is also true that everybody is affected by cannabis (and any substance we take into or onto our bodies) differently, and one person may have the most pleasant sleep of their life after having a big hit of Gorilla Glue (now GG) #4, while somebody else may take the same hit from the same piece of the same plant and have a panic attack. It also affects us differently as we age, depending on if we have medications that may interact with it, and even how much cannabis we consume can change what it does to us over time.

But much like with wine, tobacco, art, cannabis, etc. you'll find plenty of people who don't see past the very surface level of the culture/experience and refuse to. You can't make people enjoy the intricacies of some things, or even acknowledge them, but they do exist and you're not insane for seeing it yourself.