The front runner does sit much higher. Here is the Rhino Rack on the GX470. It seems like it sits much lower to the roof, I really like that. The only issue is the backbone system for the 470 either isn't imported to the US anymore, or has very limited availability. I am checking to see if it is still available. If your priority is low profile what is your reasoning for not going with a prinsu or sherpa style rack?
Yes, the RR definitely sits lower than the FR on most vehicles, I think the lower it sits the better it looks as well. I'd check directly with Rhino Rack about the Back Bone for the 470. I know they've struggled with inventory this year due to Covid so things are backed up or altogether out of stock that usually aren't.
We had a Prinsu on our TRD Pro 5th Gen 4Runner and I loved the look. The reason I'll never own another one is due to a few major shortcomings. For starters, the way that they designed the foot mounts is a joke. Using small OD spacers stacked underneath and balancing on an angled aluminum extrusion is terrible. Your lack of water intrusion/leaks rests solely upon how much sealant you globbed into the mounting holes and most have to redo it or add more annually. This is also an unsightly solution and PITA to remove/clean up. The black hardware they provided had corroded/tarnished in under six months and the powder coat had started to flake on the edges in places almost immediately. Granted this was the very first modular rack of it's kind so some leeway is given to the execution but they haven't improved upon the design since its inception and now there are better similar options available such as Sherpa, SSO, LFD, Victory, etc. They also use a much smaller 1/4" hardware in their t-slots so you have to come up with the majority of your own mounting accessories instead of being able to use the many available form FR or RR.
In regards to the other modular racks, most have a better mounting design for the feet and an actual seal so that's a plus, but I find issue with most either because I find their side rails too busy or because their wind fairing doesn't follow the lines of the windshield and those little things bother me. If I can't find some pleasure in the form of something I am going to spend $1K+ on to bolt on my vehicle and to be seen daily then I can't bring myself to purchase it, it's as simple as that. I had high hopes for the Sherpa Rack but the angle of their wind fairing is majorly off if you ask me. Another option soon to market is that from ProSpeed Rack, they are popular with the 100 and 120 Series trucks and I find their prototype for the 460 rather pleasing, I guess we will see what the final version looks like soon.