A modern ~550-piece set, also from a line aimed at kids, not one of the adult-aimed models: 3 minifigs, fills 1/3 cubic foot at best because 450 of the pieces are little 1x1 and 1x2 plates or similar. Finished set's too small for even kid hands to get in and play. If it gets messed up more than a very tiny bit, you'll probably have to re-build from scratch, because the construction is... very CAD, I guess. All surfaces clad in smooth bricks if at all possible, making adding on awkward.
The modern ones do have more cool mechanisms and gadgets, though. Also they include extra pieces for the small ones now, and more sets come with a brick tool. Those are all nice changes. But the sets themselves seem to be tuned for inflating part counts and looking nice on a box, not for play.
428-piece, 1-foot cube, $55, 4 minifigs, 1994: https://brickset.com/sets/6571-1/Flame-Fighters
540-piece, 1-foot cube, $69, 5 minifigs, 2022: https://brickset.com/sets/60320-1/Fire-Station
LEGO just has a much much larger catalog now than they did back then (200 sets vs 800 sets.) But the classic style sets are still there for you, if that's what you want.
Those outward-sloping windows in the 90's set were the bomb though, useful in so many cool applications - (star)ship bridges, towers, and the like. :D
EDIT: still, even if I have a weakness for even older fire sets, I acknowledge that the modern lego fire stations are very good toys. My son has spend countless hours playing with the 2016 version [0], which is incredibly playable, and whose fire truck is the best.
it's essential to organize them otherwise locating the piece of interest becomes too frustrating and time consuming. we use a stack of tool boxes from the hardware store to organize ours.
I help my kids by organizing their pieces by colour, with an extra box for "bits". So there's a grey box, red box, etc and a box full of minifigs and assorted non-building accessories.
My kids also have a lot of Legos (by volume, more than I ever had). When engaging in free play (i.e. not building a new set from the instructions), I find that the things they make tend to be much smaller than many of the things I built when I was a kid.
I think this makes sense. When I was a kid, for the most part I had a bunch of bricks, a bunch of girders, a bunch of plates, and a bunch of smaller, more specialized pieces, but the latter were used more for adding detail. So it was relatively easy for me to find the pieces I needed to make something decent sized and them embellish it.
When I look at my kids pile of Legos, it looks like 90% small, specialized pieces. As a kid, I remember spending a lot of time looking for that one piece that I knew I had if I could just find it. But nowadays, that situation is far, far more common.
The specialized pieces make for great looking creations on the outside of the box. In theory, they should also allow for great looking creations during free play, but in practice it ends up being too much trouble to find the pieces you need. And at that point, a new set looks even more enticing than spending all your time searching for pieces, so...