The tab refresh issue appears to be sporadic, it might not be a hardware issue or a RAM issue, but a programming issue.
Some people are perfectly capable of opening a bunch of tabs, and some people aren't. Sometimes they refresh, and sometimes they don't. Sometimes there are other apps open, sometimes not.
If the hardware is capable of doing it once, it should be able to do it consistently, in terms of what the phone is physically capable of doing with the amount of RAM it has.
This feels more like a RAM allocation issue, than an actual RAM hardware issue.
As others have pointed out, there are plenty of phones out there with 2GB ram that are laggy and junky feeling. I'd take a phone with 1GB of RAM that's programmed well over a phone with 2GB of RAM that's not any day of the week.
I don't think the phones need more RAM, the tab issue is legit, but out of all the things the phone does really really well, the tabs should be cake.
It could just be that there is some misguided soul at Apple who feels like this is a feature not a bug, but it's inconsistent and it needs to be changed. I'm sure the phone is perfectly capable of keeping tabs open, at least a few, consistently, I don't think this is a hardware issue at all.
I can't force it to happen either, it just does it when it feels like it. However, it does do it every single day. I posted the video as an example of the problem, not necessarily to say that doing exactly as in the video would replicate it.
I can have 15 tabs open and it won't do it, yet sometimes I can have a few open and it will. It all depends on the websites visited, and other background apps.