Agreed, unless you're willing to spend a bit more money on products or go the DIY route. You definitely won't really find any speakers containing 12", let alone 15" woofers in floor standing configurations these days. Unless you go Cerwin-Vega, a lot of people seem to really love the XLS-215s.
Now you can still find pretty good speakers, even smaller ones, but to have good bass, you definitely need a larger driver or a well made subwoofer to go with it. Especially if you want to reach down to the 25Hz and below range or just want more SPL. Plus, on top of that, your room can effect the bass greatly, thus the need for more than one subwoofers can be ideal. Rooms can be a pain in the butt for audio like that. lol
My room for example, I have two 8 cubic ft. subwoofer cabinets, with two 18" Dayton RSS460HO subwoofers in dual opposed configuration for each cabinet. Up front, holding up my main left and right speakers, The Elusive 1099s, and the bass response is great at my listening position, even better at the back wall, but in a couple of spots in the room, you will notice it being quieter, because just how the room effects it. I used to have these stacked in a corner, but now since I've changed things up, it helped balance it out better than before.
Though yeah, you can still get great stuff, but it seems in general, the mass produced items that people can actually afford, doesn't seem as well as it used to. I always want to facepalm anytime I see those systems at Walmart or Best Buy, where the cheaper systems claim they have 1000 or 2000 watts of power, with small tiny speakers. Like seriously, so much gimmick... those things wouldn't last three seconds if I were to hook them up to my amps. lol