Why?
If you need a media converter, router, and wireless access point anyway, there are obvious space and power advantages to combining these functions into a single device.
I could see a concern about performance, but from scanning online reviews, it seems like the Turris Omnia performs just fine.
> A router should ... > A wifi ap should ...
Instead of just stating your beliefs as if their truth is self-evident, please offer some rationale.
In my field, "toy" is anything that costs under 500 bucks. If we want a wireless interface for OOB, we'll add an opengear LTE gateway device.
The router I mentioned in the earlier post consumes 5W of power and is the size of a pack of cigarettes. It looks like a toy, and is under $50, basically disposable, but is much more stable and bug free than home routers you can buy from $85-275 at Best buy which integrate wifi capability.
The consumer market for cool looking multi band $200 routers with spiky antennas coming out of the top is, in my opinion, ridiculous.
As for the dedicated wifi side, ask any professional who uses (on the cheap side, ubnt) or xirrus, ruckus APs in environments with thousands of clients whether wifi aps should also be routers. They'll have a good laugh at the idea.
Personally, I was thinking to configure network with ER-X for myself, but I quickly started to reconsider to take ER-4/ER-6 or Omnia, which seems to be few magnitudes better. Omnia is great SOHO router, it has better transfer over the air (5GHz on Turris it's between 900-950 [0]) than ER-X in eth-eth (700-800 [1]). If you aren't scarred of having a all-in-one device[6], then it might a great choice if you would like more possibilities, e.g. to setup few more services directly on Turris (i.e. PiHole, Syncthing) with mSATA disk, instead of using RaspberryPi with SD card (:scream:) for this purpose. In terms of pricing (for EU customers) pricing does not sound that bad (if you also looking to have a WLAN network), because ubnt ER-4/RaspberryPi 3B+/UAP Lite (note, it's slower MIMO 2x2) [2][3][4] is about 260+ pounds, for Omnia 270+ pounds.
[0]: https://bluegadgettooth.com/best-openwrt-router/
[1]: https://www.mbreviews.com/ubiquiti-edgerouter-x-review/
[2]: https://skinflint.co.uk/ubiquiti-edgerouter-4-er-4-a1749252.... (~160)
[3]: https://skinflint.co.uk/raspberry-pi-3-model-b-a1785657.html (~30)
[4]: https://skinflint.co.uk/ubiquiti-unifi-ap-ac-lite-uap-ac-lit... (~70)
[5]: https://skinflint.co.uk/turris-omnia-2gb-a1520592.html (~270)
[6]: I have heard following rule of thumb, that networks should be organized to have dedicated devices per given resposibility instead of having such router-switch-nas-godzillas, because of easier replacement in case of failure, maintenance, etc. etc. (just like in microservices architecture).
Just curious, why? (You just mentioned "shoulds" and "dos", not "whys")
Have a router supporting weird configurations like CenturyLink gigabit gpon service, which if you don't want to use their terrible gateway device, requires a unique vlan tag on the wan interface.
Ability to have a router that is Debian under the hood.
That 800Mbps won't do much for a 10 Mbps ADSL circuit, or even 100 Mbps cable. Though if you can saturate that, props to you.
A ubnt edgerouter-x is good for up to about 800Mbps of NAT and runs an os derived from Debian and vyatta. Or something like a mikrotik rb4011.
Then buy a dedicated purpose wifi ap like a ubnt uap pro that does dual band 802.11ac.
A router should be a thing that has 1000baseT ports on it, maybe an sfp or sfp+ cage and no wireless. A wifi ap should be a thing with no routing functionality that serves the purpose to bridge a wifi client device at layer 2 onto some specific section of Ethernet fabric.