I run the speedtest.net app on my iphone7plus and get download speeds of 95 Mbps and uploads of 36/Mbps.
I tether my laptop to a personal hotspot set up on the same device and run speedtest.net in a web broswer connected to the resulting wireless network and get downloads of 16/Mbps and uploads of 36/Mbps. This makes no sense. Why would upload be throttled and not download? I don't have unlimited plan and I have plenty of data left in my account so the download speed on the device should be correct. Are you doing something in software at the hotspot level?
What is going on here? Something stinks.