I wouldn't be as critical when it comes to making only demands that will be accepted. That's not really manipulative IMO, and Swiss authorities were also very open about doing this.
Announcing a short lockdown then extending it (when it was clear from the beginning) is more problematic - basically, giving people false hope because they know that telling people to lock down for 3+ months would lead to a large number of people either rioting or ignoring the rules. Conversely, I suspect that some of the reductions in lockdown strictness are there to reduce the risk of dissatisfaction/loss of compliance, not based on what is safe.
The biggest problem are the outright lies (e.g. about masks not helping). This may have helped alleviate the shortage, but at what cost? The next time authorities say "you don't need X", people will remember and depending on other evidence, fewer or more will take it as "I definitely need X".
As a specific example, schools in Switzerland will reopen tomorrow, with the government claiming that this is safe because children don't spread it much. This may or may not be based on science (there are contradicting studies supporting either side), but because I know that I cannot trust the official statements, I am assuming that the motivation is letting more people get back to work, and expect a spike in cases. Thus, I'm restricting myself less now than I would be willing to if I could reasonably expect the situation in three weeks to be better, not worse, than the situation now, and I'm sure I'm not the only one.