You're comfortable in your job and good at what you do. You'd be happy staying where you are for the next 30 years until you're able to retire. You don't want a promotion, more responsibility or any change. You just want to stay the same.
Is there anything wrong with wanting to maintain the status quo?
No, there is nothing WRONG with it. You're entitled to want to live the life you desire.
But, if you think you can stay in the same position without climbing the corporate ladder, you may be in for a rude awakening in a few years. You can stay on the same rung of the corporate ladder for a few years but something has to give.
The problem with not wanting to grow in your career is that you will want to receive raises as the years of service pass by. The higher your salary gets, the more likely you will be forced to get off the ladder or climb it.
At some point, a younger person can be hired to replace you and will cost the company less in salary. That younger person will be more productive, have more energy and be able to adapt to technological change better than you.
So stay in the same position if you must. But do not complain when you're "downsized" in the future. The only way to decrease the risk of being replaced is to climb the corporate ladder and take on the responsibilities and duties commensurate with the salary you earn.