Yes, balancing the game is extremely important at all stages of development.
Everyone *****ing about content probably knows in the back of their minds that TW has a team of people pushing through new content, but isn't satisfied with that knowledge. They disregard the fact that implementing balance changes is, in general, simply a numbers game and from a technical standpoint is very easy: the hard part of balancing is finding the solution, not implementing the solution.
On the other hand, content is technically demanding and takes time and far more skilled labor.
What is currently happening in Bannerlord is that they are balancing the game and creating new content at the same time, which is the best use of their limited resources. It doesn't take many people to implement balance changes, and the people brainstorming balance changes should be different than content developers anyway (Pro Tip:you never, ever want the people creating content to be the same people making balance decisions).
So yeah, like all large gatherings of passionate fans, most loud voices in this community are either misinformed, overzealous, or just plain biased and wrong.The sky isn't falling, the game is being developed, balancing the game isn't slowing down content in any meaningful ways, and patience is still a virtue.