I don't know why you have all those requirements. I have a different view of a "good" WiFi router/system. Let me explain:
- 1Gb up/down can be handled by many routers, on LAN. 1Gb on WiFi is currently not needed for most devices.
- What options specifically do you need? The more options in consumer routers - the worse implementation of each one.
- "Robust" and "consumer router" usually do not live well in one sentence, especially newer disposable models.
- 10Gb and LAGG support... for what reason? NAS? Many have this option.
- 4+ ports are not a problem, a 8-port dumb Gb switch is $20, smart Gb switches (even with PoE) start from about $70.
Think this way:
- Web browsing experience >150Mbps is all the same. Very few web servers will send you data back with >100Mbps.
- Mobile devices don't need >100Mbps connection. 4K streaming on a small screen is a bandwidth waste, for example.
- Mobile devices don't do large downloads, so no extremely fast WiFi is needed.
- Computers/Servers/NAS is best to be wired, no WiFi will give you the same performance.
Few people got Netgear R7800 on sale for $120 around Christmas. This is one of the best performing AC routers in term of WiFi speed and range. It is extremely reliable too, based on user feedback. It is Qualcomm hardware and fully supported by OpenWRT. Take a look, may be a good option for WiFi. AX routers are work-in-progress, you'll be the guinea pig. A paying guinea pig. And you'll be lied to about what technologies your router currently supports. Do you think RT-AX88U supports all WIFI 6 specifications? Think again.
If your budget is high enough, think about wired router + switch + access points from small business segment. A nice all Cisco, Ubiquiti or mix-and-match as per needs system will be really "robust", secure, flexible, upgradeable, configurable, etc. system. The performance will be much better than any consumer router you can buy. If you need an advice in this direction,
@Trip may give you all the options available.
@coxhaus is a Cisco guy, he knows what works well from this manufacturer. I have played with a lot of consumer routers and none is perfect. They all have flaws, some very serious ones. Finally had the time to arrange something better for my home and there will be no coming back to consumer products any time soon. "High performance", "enhanced performance", "optimized for gaming", "better than ever"... forget about marketing BS in consumer segment.