The only reason you should be less hands on the more senior you become is one of the following:
* objectivity - This means stepping back and taking a bigger view. You must criticize things you would never criticize before and ask better questions.
* administration - When you hit management or principle level your time becomes filled with meetings and things to do. You also have a lot to account for plus other additional responsibilities. These things will take up most of your time and leave you with mental fatigue.
The higher up you get the more time at work you should expect to spend. Although promotions come with raises expect your pay rate per hour to actually decrease with each promotion until you achieve high senior management. Just become you have more administrative and people oriented things to do as you elevate doesn't mean you get to abandon coding. It just means you need to account for that time somewhere else. If this remains your line of work you have to maintain your proficiency.
When people get burnt out its typically not from doing too much work, but doing too much work they don't enjoy. That could mean too much administration or it could also mean writing code that feels ethically dirty that knowing causes harm with in terms of tech debt or in terms of real moral harm in the world.