When there's a vaccine that can save loved ones lives literally just arriving, then yes, it is of course fear. To lose someone this far into a pandemic with the solution literally on our doorstep would be ultra painful. All that separation and lack of time together for nothing. Why would anyone not be nervous?
On a side note, I've had a slight inkling throughout this that those most opposed to lockdown restrictions often have either had the virus so they're no longer personally fearful, or they don't have any notable vulnerable relatives that they're particularly concerned about - be it cos they've passed on or they work comfortably from home or they're retired and safe and sound.
Of course there will be exceptions, but I'd wager that is the situation for a lot of notably vocal sceptics. They feel secure, others don't. Not everyone, no, but almost certainly a fair few. Not that i'd particularly blame them either. If I didn't have vulnerable relatives i'd probably be a lot less concerned...or if I had and they'd already had it and recovered, or my immediate family had gone through it I might feel different too.
My point being is that everyone has different circumstances. Fearing the loss of loved ones is a perfectly good reason to want to lockdown and protect them. I can certainly go without restaurants, cinemas etc for a few weeks if it means there's a greater chance of my loved ones being protected and getting a vaccine. Freedoms are absolutely nothing if the people you want to share those freedoms with are no longer here. Not unreasonable really.