They feel like they are owed various things from their children because they raised them. There is no reason possible to justify cutting them off in their minds. Last Christmas I said I wasn't going to the family get together because of COVID concerns (many anti-vax relatives) and my mom called me, alternating between crying and yelling at me because I was "being inconsiderate".
it's not new but it's becoming more common given how stark there is of an ideological divide between older and younger people right now
don't wanna get into generational war or anything, because this is mostly a result of stuff like the housing collapse and wages staying stagnant since the 1970s. Older people largely represent survivors of a easier time to be alive (if you were white and not poor) and that's coloring their impression of the world, even now