That is true. Now imagine the size and scope of the outrage when people are forced from plans they don't like AND are through increased taxes pay for a radical expansion in Medicare. The next shoe to drop is that Bernie's plan is unfinished and unready for implementation. Republicans will do all they can to sabotage it too. Delays in service, mistakes are all going to create a backlash just like what happened with Obamacare during its roll-out except on a larger and more meaningful scale.
Forcing people from plans they don't like is a stupid idea. Then too, Bernie's half-baked plan is amateurish and an embarrassment to anybody who supports universal healthcare. Also, Bernie has no experience in getting things done. His plans are a disaster on paper, much less if ever implemented.
I support shifting the healthcare system to Medicare but not in the way that Bernie most ridiculously proposes. Elizabeth Warren and others propose giving people the choice of buying in to Medicare or not. This is a much more rational and politically savvy proposal.. Somebody with experience and leadership ability should oversee the shift to universal access to healthcare. This means somebody other than Bernie.