Everyone's use case is different. Currently at twenty one years of ownership on my '99, at 435k present, light off roading (once per year and occasional medians and concrete obstacles around town) and a trip to Moab a few years back. I've put 30k on my rig in the past 12 months. Yawn. This is a summary of my maintence log.
Complete front suspension swap at 200k, then again at 400k.
Ironman mid package at 200k
Rear suspension control arms, panhard 300k.
Alternator. on third, replace at 200k interval.
Fan clutch, and bracket, 300k
Serp tensioner, every 150k
PCV and grommet every 150k or so.
radiator, first lasted 250k, i'm on my fourth at the moment, small leaks forced replacement.
steering rack, 200k, then again at 400k, this time with new steering pump hoses (only non oem part on my rig, a Sunsong unit, pleased so far)
Timing belt, water pump 100 to 110k, never an issue, and all associated parts.
CVs, use dependent. At 400k, had a little flange slop on PS axle. Installed both front CVs and new flanges, let's roll another 400k.
Fuel filters. Every 150k.
Valve cover gaskets, spark plug seals 300k
Starter, as needed. Currently on my 4th starter, PITA, but the cost of loving this vehicle.
Coil packs. Every 200k. Just suck it up when you feel them getting ready to go.
Spark plugs, get real plugs, not Chinese! Every 100k.
Misc hoses, at 250k, as needed on engine.
Engine mounts, trans mount, 250k
New driveshafts 400k (don't waste time and money on replacing ujoints, I tried that)
There's more I'm missing for sure, but the above large item timeline is my experience. The suspension refresh is very satisfying and absolutely worth it, especially when you can do the work yourself. I started out only knowing how to change oil twenty years ago, and I've now been the only person to work on my Cruiser for the past ten years. THANKS IH8MUD community. Glad to say I did a successful engine swap on a friend's 01 Cruiser a few years ago, (blown head gasket from not monitoring fluids, and crappy indy shop maintenance).
Once you wrench, you won't let anyone touch your rig. Ignorance can be bliss for you guys that just go to a shop and trust someone else to do the work (I'm jealous of you, to some degree.... )
I do rather enjoy pulling up to the prime parking spot at my local Toyota dealer; sales people see what I'm driving and know that I'm not there to buy anything. "Just here for parts!" as I proceed to walk by the crowded lounge area to the parts counter.
I will say, Know Your Fluids!!! If you are lazy and don't maintain the lifeblood of your vehicle, expensive and bad outcomes are likely. It's so simple to be on top of your fluid levels and maintenance, so just learn that and be consistent.
Cheers!