Not the first time it's happened.
Furious 7 actually did reasonably well using Paul Walker's brother for a stand-in for some scenes.
Between the stunt double, his brother and CG, it's improved over the years since actors have died during production.
Yes, The Crow is a #1 movie where the actor died during production, but it's not noticable when you watch the movie.
It looks like it was the final day of filming when you watch the whole movie.
Or better script writing to shorten his screen time.
HBO started the challenge of working with stand-ins and CG facial replacement when Nancy Marchand died.
It was extremely awkward because it was the first step in this reproduction.
Here's what it looked like:
https://www.youtube.com/watch?v=GS0DQKHMpM8
If HBO hadn't done it, others wouldn't have also done it and eventually improved upon it.
Of course, you can go super practical and entirely recast the character who will look nothing like what you expect.
Game of Thrones has recast, not because of death, but because of movie opportunities.
The fact anyone can make a movie, means that anyone can have any idea they want.
What they choose is really neither here nor there.
We can only accept that it happened.
I imagine the reason that Rogue One is the most talked about shenannigan is because it touchces base with the OT story arcs.
So being directly influential to the OT, I bet most fans would want to see a brand new actor taking Cushing's place to keep things practical instead of CG makeover.
In a world of CG, we can either move with the tides or you can fight it, lose your stamina and die.
I haven't seen the movie yet. But it won't phase me.
I've watched apes wear rubber masks only to turn green with ping pong balls all over their body with measles on their face.
I think games work out so well because the audience knows everything is CG from the start.
So suspension of disblief is simple. After that, nothing is too out of place in a universe that doesn't exist.
Like Michael Bay, I prefer things to advance.