Gigabit has such a small installed base continent-wide, that testing tools and content delivery systems are lacking. Since the purpose of Gigabit speeds are to address multiple users on a single connection, rather than a single user getting Gigabit speeds from one site, I would suggest the info you have received s indeed accurate.
I also just switched from Telus Fibre 150/150 to a Gigabit plan.
I find that I do indeed receive the 900 Mbps download speeds but only around 300 Mbps upload speed, the first couple of days it was 750+ Mbps. This applies only to my tests done on a hardwired ethernet connection.
I get no where near these speeds through wifi. I have tried with my iPhone 7, iPad (Gen 4) and a laptop that when hardwired get the full speeds but through wifi only around 300 Mbps for both download/upload. This the maximum speeds when in close proximity of the modem... move away 10-20 feet, the totals drop significantly.
I think the plan my be misleading.
I also wonder if there is a setting that is blocking the additional speed through wifi?
From the Actiontec web site:
Support for dual band 4x4 802.11ac (5GHz) and 3x3 802.11n (2.4GHz) delivers ultra-fast wireless speeds up to 2.3 Gbps*.
That is the theoretical speed assuming you have the right network adapter on your device and you are on a deserted island with no other signals. In the real world nobody gets close to that. For most people the limiting factor is the network adapter on the device and how many other WiFi signals are competing with yours. Looks like that's the case for you with the iPhone 7 which has a rated max of 450 Mbps and is likely being degraded down to 300 Mbps due to environmental factors.
I just used fast.com for the first time (usually either the Telus or Shaw - Ookla) and received 1.2 Gbps download speed but upload speed was only 220 Mbps.
I don't think it is hardware dependent (maybe for the NIC card). I get the same result with both of my desktop systems with I7 processors and lots of ram. My office laptops also get the same speed via Ethernet but are both I5's with a smaller amount of ram. They are noticeably slower than my home desktop computers.