Is there actually a washer with an easy-to-clean filter, or am I dreaming?

Short answer: easy filter access exists, but mostly on front loaders, not top loaders. Most front loaders these days have a little door at the bottom front with a drain hose and a screw-off filter behind it. You put a shallow pan under it, twist the cap out, and pull the hair clumps and whatever else out in about five minutes. That's exactly the setup you're describing, and it's become pretty standard across brands. My LG has it and it's the least annoying part of the whole machine. If you can live with a front loader, that's the feature you're shopping for. The catch is you have to wipe the door gasket and leave the door cracked or you'll get a smell, and some people hate bending down to load it. On the top loader side, the news is less good. Almost every modern top loader uses a self-cleaning pump filter, meaning there's nothing for you to open. That's mostly fine for lint and hair, but sand from soccer gear is the enemy here. Sand is heavy enought that it doesn't all go down the drain, and it collects under the impeller plate or around the agitator base. No manufacturer gives you a trap door for that. You either pull the plate off occasionally or live with it. The old machines with actual removable lint filters in the tub are basially gone. The locked lid thing is unavoidable on anything new. Every machine sold now spins fast enough that the lid has to lock during the spin cycle, that's a safety rule, not a design choice you can shop around. Some machines unlock faster than others once the drum stops, but you can't get away from the lock itself.

Two other things that helped me with the same gunk problem. First, run a tub clean cycle monthly with whatever cleaner the manual calls for, it flushes out a lot of what would otherwise build up. Second, do a quick rinse or shake-out of the sandy stuff outside before it goes in the machine. Sounds obvious, but it made the biggest difference for us with beach towels and cleats. If you want the simplest, most old-school top loader, the Speed Queen gets recommended constantly, but it's expensive, the tub is smaller than it looks, and you still won't find a user-accessible filter on it.

Gonna push back on one thing above. The monthly tub clean cycle isn't going to do much for sand. Those cycles are meant for detergent residue and biofilm, they heat water and agitate but they don't flush out heavy grit sitting at the bottom of the outer tub. I ran them religiously on my last machine and it did nothing for the gritty sludge my husband's work clothes left behind. What acutally helped was the rinse-off-outside habit, plus once a year I ran a full drum of hot water with nothing in it and let it drain slow. diferent problem, different fix.

We're on well water with a ton of grit and I got tired of fighting it too. What ended up working for me was a yearly teardown day. Unplug it, pull the hoses off outside, tip the machine in the yard and flush the outer tub out with a garden hose til the water runs clear. Takes me an hour once a year and gets out everything the machine left behind. Not a fix you can do monthly, but it keeps an older machine going way longer. I'm on year nine with mine doing that.

Lurker here, first post, so sorry if this is a dumb question. Our problem is cat litter dust rather than sand, it gets everywhere and turns to paste in the machine. If that grit collects under the impeller plate like the second reply said, is pulling that plate off something a regular person can do without breaking clips or anything? I watched a video once and it looked like you just unscrew the cap on the agitator, but I don't want to crack something on a machine I can't afford to replace twice.