Consent is an important part of truly living as equals with others. For without consent, you are being forced to do something against your will. Without consent there is no freedom. As soon as you lose consent, you become more of a slave than a free person.
It's not a very difficult concept and philosophy for living your life to understand. You agree to something and therefore consent to it. If you are not provided with the choice, then you can't possibly consent to it.
Here are some examples that really make it cut and dry and easy to visualize the difference in some scenarios of our life.
What makes sex not rape?
Consent.
Someone is having sex with you, but you don't want to have sex with them, and that is rape. It's happening to you without you wanting it to happen.
What makes a job not slavery?
Consent.
If you're working without agreeing to do that work for whatever reason your agreeing to it, not become slavery. If someone just tells you to do something roasted in a beat you up or kill you, then they are asking for your agreement. They aren't freely exchanging something in order to have you freely agree to do the work for them.
What makes a transaction not robbery?
Consent.
Just like a job, you have a give-and-take when you transact for a good or service. Someone is offering something to you that you want, and in exchange you have to give them money, or something else that they agree to. If you just take what they have without giving them what they're asking for it, then that's theft.
At the root of all this is voluntary interaction. Voluntaryism. This is a core foundation of nonaggression and actually living in peace with others. Violating this voluntary interaction is the road to greater enslavement.
And in our current times people are very confused about how to actually live in peace with others, and how to live morally.
What makes mandatory vaccination not tyranny?
It's not consent, because a mandatory vaccination isn't giving you the choice to say no.
As the image accurately portrays, the only way you can convince yourself that mandatory vaccinations are not tyrannical is with magical fairy dust. Because to do so means you're living in a complete fantasy and denial of what tyranny is.