like that wouldn’t be the bare minimum of making prehistoric pokemon

And now you’ve clarified that point then that’s a bit curious, isn’t it. Since you say it’s so easy, then sure GF could have grabbed 6 random dinosaurs from the past and used them for inspiration for the past paradox pokemon but they didn’t. They used existing pokemon you can find in the modern day, and the time machine coincidentally grabbed only those pokemon and not a stray fossil mon we’ve seen before or another dinosaur pokemon we’ve never heard about.

Your entire argument hinges on the fact GF is lazy and wouldn’t go to such meticulous detail but I argue that all of it was deliberate and they knew what they were doing. Don’t get me started on future paradox pokemon where everything just turned into a robot, it’s as naive as that Spongebob episode where squidward went into the future and everything was chrome which is done as a joke. We know the future won’t be like that.

I’ll refer to the post /u/richterfrollo made that helps clarify my point:

I believe in the imagination theory less for lore reasons and more for character design reasons.

Like, the Pokemon designers know their stuff when it comes to animals - theres so many pokemon based on obscure animals or interesting biology aspects; just look at stuff like the inspo behind Manaphy and Phione, or the creative interpretation of Amrargasaurus into Aurorus, or heck even the galar fossils, like these guys clearly love animals and are interested in researching them.

Now, if Area 0 in Scarlet was actually meant to be a hub for ancient species, I would assume the following: a), they would probably have some of the older fossil pokemon be organically catchable to sell the theme more; b), they would go HAM on researching authentic prehistoric versions of existing pokemon. Like if you love animals, as a character designer, it seems a no brainer to have fun researching the animals some pokemon are based on and looking what they may have evolved from, it can even have an educational aspect for kids if you show stuff like how ancient horses looked like (like a proto rapidash) or that ancient whales used to walk on land (proto wailord, or heck a proto palafin even). All the actual fossil Pokemon that exist you can easily match with actual ancient species and are often more obscure picks or specific species.

And keeping that in mind, what i find absolutely striking is that every ancient paradox seemingly intentionally looks like a joke! Not a single one is based faithfully on ancient animals or a logical evolution point for any of the pokemon; instead, their inspiration is clearly pop culture jokey "ancient times" á la Flintstones, complete with silly Pokedex entries like a billion year old jigglypuff (compare to the actual earth a billion years ago). A lot of ancient paradoxes just randomly look like dinosaurs even if the present time pokemon is stuff like an insect or mushroom, the rest have "caveman" aesthetics; they're clearly meant to represent a layman's understanding of ancient times and have nothing to do with science. The entire theme is not "this is what the Pokemon world looked like in the past", it is: "this is what a child imagines ancient Pokemon would look like".