i know how hard it can be to overcome those feelings about your island :[ ive got two different types of advice stuff i could give for this!
this one just takes a lot of time to come to terms with (at least it did for me), but its the fact that what truly matters in animal crossing has never been perfection- its been crafting a safe space thats all your own that you can unwind in anytime in your life, thats a constant for years! every little thing is personal to you, and that honestly matters more than the subjective aesthetic appeal of it to strangers on the internet.
however, theres another point that i think really helped land the point for me: have you ever seen the meme with homer, where he looks skinny but he's actually pinning his fat together behind his back? the photos you're seeing are essentially skinny homer. most, if not all, of these aesthetic islands i've heard about are actually far less enjoyable in game. there ends up being lag, cluttered streets, dead ends, and a generally reduced everyday play experience. theres even one popular aesthetic island that just has half of it hidden and covered in dropped items, like a dump area- theres probably many more like this one!
and remember that your glimpses of these islands are also heavily staged photos- these areas might only look amazing at that one camera perspective, but wonky in general play (like those illusion buildings and all that). some of these photos are also edited, with fancy backgrounds and general enhancements. islands do often catfish!!
i hope some of this can help!