Many good points here.
Regarding the crawling of scientific progress, it depends on what kind of cure you're envisioning. The most realistic right now is the kind of cure where we constantly need to be one step ahead of Death. Every individual "cure" will grant us maybe 20-30 more years, and by the time those are up, we'll have to figure out a way to beat the new issue that will inevitably come up. Doubtless this will some day cease to be the case, though.
Which leads us to people locked inside shells, interacting only via VR. I think that's a very plausible concern. The greater our potential lifespan, the more valuable our life becomes, which means death becomes a far worse thing. If I die now, I will lose a mere let's say 50 years of potential future life, and a 30 or so years of past life. If I die in the future after 'immortality' has been invented, my death might mean thousands of future years lost, and thousands of past years of investment as well. So yes, people will press governments (or the equivalent) to up safety measures/features greatly (driverless cars would be a simple example), and ultimately they'll stop going out of their house at all.
But there's so much we don't know. Maybe we will merge with machines, and we'll have many backups of ourselves, so if any individual token of the type 'John' perishes, it's no biggie.
Generally, I look at it more in terms of inevitability: I think it will happen, so we should better prepare for it. With the birth rates now, we're facing an economic apocalypse in the future. It's well-known and uncontroversial among economists that the population needs to keep growing to sustain the old. It's one of the reasons countries like Germany, with their birthrate of 1.5 per 2 people, are so eager to let immigrants in. But this is an unsustainable system, climate- and planet-wise. So the way I see it, unless we become immortal, we're doomed. Space travel is science fiction at this point, whereas mice are already living 5 times longer in labs. If it were cancer they'd already be in human trials.