Even if you wanted to say that some of the White liberals who supported Anderson would have gone for Reagan, it doesn't affect her basic argument.
So, no, her point is valid and using 1980 isn't any kind of trick.
Anderson was a lifelong republican, to the right of Mitt Romney, who was at first supported by Romney/Rockefeller’s wing of the GOP and he ran against Reagan in the primary before going Independent.
Republican Anderson ran as an Independent and hurt Reagan as much as Carter among the total vote, as he served as the middle ground between Carter and Reagan, a true right-winger.
This year, millions of whites just stayed home because of Romney. This year, the guy to the left of John Anderson, the anti-Reagan guy, Mitt Romney, was Jimmy Carter and John Anderson rolled into one.
Carter could only muster 44% of the total under 30 vote in 1980, and 36% of the total white vote in 1980.
Obama won about 40% of the white vote, and worst of all, Romney left millions of white votes on the table which hurt us down the ticket.
Romney was a disaster for republicans, and when you look at who he is and his relationship, or lack of it, to republican politics, you wonder, how in the heck did this fringe character take over the GOP?
People will go to any length to keep the rino dream of the conservative hating, anti-Reagan, Romney, alive.