Correct, though binge+ box claims it has 5ghz band, but seems, it has wifi 1x1 antenna as oppose to 2x2 antenna most mid and high range phones have... and some cheap wifi hardware in box to save costWell As far as I have seen the speed test results depends on the server we or app uses...We can change the server and check the speeds...
For wifi it depends on the wifi version of the gadget ie : mobile ,Android box supports...I have checked in my vivo u20 and Realme5 pro..if Both shows 45 Mbps then my New Redmi Note 10 pro shows 53 -55 Mbps...in 100Mbps plan older was showing up to 56-57 but RN10 Pro was showing 100-103....The old mobiles have older wifi version which have PHY 72 upload 72 download...RN10 Pro have wifi4 version and PHY 150 download 150 upload...
I think Binge Plus having older wifi version... thatsy it gives less speed in wifi and bit heigh in LAN...
I feel like LAN port is also limited to 100 Mbps not 1 Gbps, thats why speed shows less in binge (unfortunately I cant check port connection speed because its connected thru unmanaged 1 Gig switch)
For speed test.net, I always get constant results in phones, Ipad, laptops. I always choose auto for sever selection. You broadband in my area is kind of constant in speed according to BB plan even in peak hour too.