Why SRB2 has lower priority then SRB1?

Hello.

Can anyone tell why SRB2 has lower priority then SRB1?s

Any example?

Because SRB1 carries the RRC control messages which are required to maintain a healthy connection.

Who takes care of this priority?

Means, who performs evaluation that this message is for SRB1 and needs to be prioritized?

All the message originated from RRC layer will be either srb0 or srb1.
Example of srb1 - measurement report, rrc setup complete, rrc reconfig complete etc.