Not really.
It actually takes a not a complete pile of shit router to handle 1Gbps of routing/NAT traffic.
Archer C7 are pretty shit with only a single core CPU, probably barely any RAM, when you’re loading third party firmware on could well stress it way beyond its already limited capabilities.
A simple Google shows people with C7 struggling to get 2/300+, wired or wireless as not a LAN issue. I’d say it’s entirely possible the router is the problem in this scenario.
I am an avid RCS supporter and have been for years, but I don’t think Apple need to open up the whole app.
Apple does not have any real lock in for messaging apps, people can add their own to the App Store easily, there are no rules against this. WhatsApp has existed and been the primary messaging for many for a decade and Apple hasn’t ever tried to kill it.
For legitimate security reasons does not allow other apps to takeover SMS/MMS etc. I am over the moon Apple will finally allow real interoperability between platforms, that was the issue and it will be fixed, no need to bloat it.
I drive a lot for my job, a lot in rural areas with no mobile signal. I’ve never had to use it, but I have seen the SOS symbol and it is reassuring to know if I needed help I could get it.
Depending on price, I’d seriously consider subscribing to it, maybe one to bundle with Apple One.
Doesn’t look like there are obvious signs of physical damage.
I’d take it to Apple, play dumb, don’t mention the dice and see if they’ll warranty repair it.