No that isn't required because the 5 GHz band gives speed test results of around 90-95 Mbps consistently.
It may due to the router selecting a bad 2.4 GHz channel.
Try changing the 2.4 GHz WiFi channel to one of 1, 6, or 11 rather than setting it to auto. These should give you a better speed.
I also facing same issue from few days. I getting slow speed on speedtests on laptop by lan cable but 94+ mbps speed on mobile.
The problems would sustain till the time Jio allows change of Channels and Width. You might be surrounded by too many 2.4ghz routers. I have the same router and for me the speed difference is negligible. If i am near the router, i get the same speeds as 5gHz. The difference between both the modes would be just 1-2 sec delay in ping. Even at the farthest location (5 rooms away), i am able to get 50-65mbps on 2.4ghz