No. The blame is on the players AND the manager. A lot of things are true in your comment, and this makes coaching Barcelona at this point in time a very hard task. This does not mean Valverde is not part of the problem. He very much is, because of the decisions he made. He is not a victim of the 'club de amigos'. He is one of the biggest supporters of it. This has been the case in the last 2 years. He loves veteran, experienced players, and doesn't really care about developing young talents.
It is possible for most of the things you say to be true, and also for Valverde to be unfit for a club of our stature. A manager who bottles a 4-1 lead, and then goes on and does even worse next year, is clearly out of his depth.
Yes, we have some issues in the team, and yes, Valverde added many issues on his own, on top of the existing ones. Only in this way you can have historical disasters like the Liverpool game. Leadership from players to manager is almost non existent. Many complacent veterans who don't run, and a coward manager who's out of his league among Europe's best. Add this, and also add a vision-less board and you have the 3 major flaws of this team.
Lack of workrate and intensity, average cowardly manager, and spineless, vision-less board. Put these 3 together and that's how you become a joke in CL with over a billion euros worth of players time and time again.