Rhaenyra has absolutely had character development. But the development isn't her growing into what others are telling her she should be, it's her becoming more and more like her uncle, succumbing more and more to his brand of Targaryen exceptionalism, with every episode featuring an escalation of what she tries and succeeds in getting away with. Her taking what she wants, forcing a KG to break his sacred vows, lying about it on her mothers grave, and getting the hand dismissed over it, is development. And even her best friends sees this as something she would not have done in episode 1 when they were gossiping about the loose women in the court and her only sins as a princess were being late and defacing books.
Growth isn't always defined in terms of being one thing one second and something completely different another second, growth can also be defined in terms of the scale of little characteristics that grow from seeds into full grown trees. This is what we've seen from Rhaenyra these first 4 episodes. Wanting to speak in the small council in episode 1 but remaining quiet, to speaking up but getting shut down in the small council and at dinner by her father in episode 2, to calling out her pops on hypocrisy in episode 3, to outright dictating terms to the King regarding the second most powerful man in the realm.
On another note, rejecting advice, rejecting archetypal norms being presented for you to follow, and instead choosing to challenge and step into a different role (for instance, tackling the brothels the way prince's do) is also growth. Growth doesn't mean someone tells you to do something and you do it, forever changed by following their suggestion. Sometimes choosing not to do it shines a brighter light on the tenacity of your resolve and who you are as a character. Being presented with an off ramp but continuing down a path of your own choosing. The lengths Rhaenyra will go, including up to self sabotage, to not fall into the cycle of being locked in a castle pumping out heirs like her mother and stepmother, is development of her character. It's actually a sharp contrast in the development between her and Alicent.
every time he gets mad at his brother, he huffs and puffs and gives him an out - everyone knows it
