You might want to take a look at the original short book "Extreme Programming Explained" by Kent Beck and form your own opinions.
The main thing is that every single change needs to be vertical in nature. You are never making stories where you say, "I'm going to add this functionality to a library. Later we'll add the UI and finally, we'll add the data to the DB schema and then ship". But it means that you need to design your software quite differently in my experience.
Even just from the DB level, you need to have things set up so that you can make very quick changes safely. You need to be able to change the schema, do migrations and make sure that rollouts can be done safely -- and it needs to be done on the order of an hour or so. That probably seems impossible to some people, but it's one of the reasons you can't really take a legacy project/team and say, "From today we are doing XP!"
Similarly, you need to be able to make changes to your infrastructure quickly. So if you have some big set of microservices and each small change requires a signoff from some group somewhere: well, it's not really going to end well. You need to be able to make that change and get everything working end to end in hours, not days/weeks.
One of the things that a lot of people have difficulty with XP is that it's generally incompatible with nailing communication specs to a wall. One day, I may need to add something to the API. The next day I need to be able to change that API. If someone comes to me and says, "You need to know everything you want this API to do for the next 3 months so that we can have a sane versioning system", I'm totally screwed. I don't know what I'm going to need next week let along 3 months (or whatever) from now.
For a lot of people, this stuff is just way too different to deal with. XP comes with the subtitle, "Embrace change". It literally doesn't work unless you decide to go whole hog on it. I've been successful introducing it to some teams, but on others I don't even try.
To try to answer your question a bit more closely... it's probably not what you imagine. It's not like you have people telling you how everything is going to work all the time. However, you are constantly thinking about it. Sometimes you'll have developers say, "I want to work on X" and you'll respond, "Why? How are we going to give value with that work?" And then they think about it and say, "Well, what if we altered the work flow here. That would allow us to remove this stuff. And then if we added this, it would mean that we don't need that library any more", etc, etc, etc. And instead of telling management that today "We removed some technical stuff" or "We got rid of some old libraries", we say, "We improved the workflow for the customer which enabled us to simplify the code at the same time".
This is why I was asking - I still don't fully understand if this is a "XP thing" or not.
Doesn't this reflect some much deeper problem with the product planning or management? If you literally can't plan even a week in advance that suggests there simply is no plan, and even the most scatterbrained business environment doesn't change that fast.
I'd say customers being able to stick to a coherent story about what they want for more than a week would be a key need in any successful IT project.
Methods like XP embrace that by allowing requirements to change over time, to account for the customer accumulating more knowledge about all three areas.