He can fire appointees. FBI agents are not appointees. They are civil servants.
The President cannot just go around firing civil servants.
That and people forget that DC voted 92% for Hillary and 93% for Biden. DC is chuck full of government worker drones who are democrats. Some say FBI workers are 90% democrat, CIA is even higher.
How can one man, Trump, fix a problem that happened over five decades? People are expecting the impossible if they think where we are is Trump’s fault.