Ha, I started reading this thread, then had to double-check the original date (huh, just a few days ago). You mentioned that your laptop was ~10 years old. I chuckled, because most of your observations/complaints about the latest MacBooks are about that old, too! Where ya been!?
I have the latest, greatest WiFi, but I think my Ethernet is still faster. I'm with ya there. But I rarely need to move a lot of data, so when I do, I use a $13 dongle (which lives on the end of the Ethernet cable, it's a simple, inexpensive work-around). Otherwise, the WiFi is more than adequate. You probably need to upgrade your WiFi to a mesh network. You really will see a huge improvement in performance.
MagSafe is back. That's all I really missed, when it was gone for a few models. I'll use the headphone jack once in a while. My MacBook Pro has HDMI, and some slots for cards, but I never use those. They got rid of that awful Touch Bar, so the MacBook I have now is without a doubt the best I've ever owned. I don't know what other jacks you think you need, but you probably don't, if you can give an honest effort into rethinking your computing style. If you're not willing to upgrade your style, then there's no reason to upgrade your computer. (Just because your old Mac can't upgrade to the latest OS, doesn't mean it'll stop working. You could probably use if for
another 10 years!)
Mac's are crazy fast now. I've never heard a fan. It's stays so cool, I honestly don't know how it runs. The only time it gets a little warm is when it's charging. But it charges so fast, and lasts so long on a charge, I rarely have to. And mine isn't even the latest: the newest ones are even faster, with even better battery life. And I'm not even addressing what the OS can do now. Really, really amazing stuff, coordinated with iPhone and iPad. Have you even tried out any of the new software features?
Point being, yah, some of the old goodies are gone, which you could learn to leave behind with a little effort (like by practicing more with a track pad and ditching the mouse, etc), but your "review" is not particularly fair (IMO). The hardware and software tech in the latest batch is really incredible, and you're kind'a overlooking all that, instead of enjoying and appreciating it, because you're still using your Mac like you did 10 years ago, and you're soured on the fact that you have to buy a cheap dongle because you still want to use the last mouse in existence.
Give the new software features a real tryout, which are only possible because of the new hardware. Apple can't keep supporting 10-year-old computers for the three people that still want to use them, they're on to bigger and better things, much bigger and much better, and you can be, too!