Considering switching back to shaw.... need some advice

[wireless]

We were long time Shaw subscribers and were happy with the service until we moved last year. In our new neighbourhood, the shaw internet was not very good and would really bog down during peak hours. Fortunately (I thought) Telus pulled fiber to our house shortly after we moved in.

Made the switch to pure fibre last month. Install went OK considering the tech couldn't come in the house. Here is how it was setup (aplogies for the laymen terminology):

- fibre optic reciving box is mounted in garage (white box)
- Modem is next to it connected with a cat 5 (or 6, haven't looked too close) cable
- Modem is tied into the house through existing coax cables
- Router is in the living room. Coax cable comes out of the wall, goes into some sort of converter. Cat 5 cable comes out of the converter and goes to the router.

No issues with the TV or home phone.
Internet speed is appalling. Routinely get 30 to 40 Mbps download. I thought maybe it was an issue with the wifi, but when I plug in to a router in the living room with a network cable I get the same speeds.
I'm getting decent strength throughout the house. Doesn't seem to matter if I'm standing directly over the router or on the other side of the house, speeds are the same.
I thought maybe it was due to the coax wiring in the house. So i ran a 50' cat 5 cable from the modem in my garage to the router. No improvement in speed, even when I connected various laptops to the router. If I'm hardwired to the router, which is hardwired to the modem, I should be getting better than 40 Mbps?
When I log into the modem and run a speed test it shows 400+ Mbps. So it appears it's something downstream of the modem.
In addition, devices are frequently kicked off the wifi. We have to power off the router at least once a day in order for devices to reconnect.
Internet frequently drops out mid zoom meeting (kids are schooling from home, and I periodically work from home). It's embarrassing when you're hosting an online meeting and spend more time connecting to it than participating.
My smart devices either can't connect, or have trouble maintaining a connection with the wifi.

My wife and kids are begging me to switch back to shaw. Does anyone have any advice? I'm not quite ready to throw in the towel, but if I can't resolve in the next week or two, I'll be switching back to shaw.

Thank you.


More...