1. Well I have 10 EHDs. Had 5 large self-powered drives going back to around 2009 or 2010, then when I got the hopper 3 I wanted to switch to small buss powered drives, so I got 5 portable drives, (and a powered hub) let the Hopper format them, then copied shows from the big old drives over while taking the opportunity to clean them up - ie: sorting the new disks into cleaner categories. This was done using a Linux system and a Bash script. No issues encountered. That's not to say that nothing will ever go wrong for anyone or you won't find someone complaining about any imaginable problem on the internet. It's good to be forewarned by the internet, but in my experience, most of that doesn't happen to any specific individual.
2. 50 calls to Dish is about 45 more than I've had in the last 25 years. I had an old analog cable system in the 80s and 90s. Around 2000 I had Dish come out and I pointed him at the connection between the cable company and and the wire the home builder put in the home and said - connect it there. Then around 2008-2010? they came out and put a 722K in in place of the old SD receiver (and TiVo) and then they came back about 2 years ago to put a Hopper 3 in. (They claimed my 722K was just way too old.) Besides that I think I called them once or twice because I couldn't update my credit card online.
Can't say anything about Google nest. I have a router I bought at Costco (around 2017?), and I have another older router that I have wired to it working as an Access Point. The two routers are far enough apart that at any place in my house, at least one of them is not shadowed by the HVAC system which is roughly in the middle, and they have Ethernet between them. They're only about 15 feet apart but that does a great job in this home.
Possibly I'm more the Luddite here though because I don't even have a TV in the shop. (And shop means my garage!)