CT surgery can be approached via two different pathways. The first is the 'traditional' pathway. It is 5 years of general surgery residency followed by 2 years of fellowship in CT surgery. The second is the 'i6' or integrated pathways. It is a 6 year residency. How well trained you are in aortic surgery depends on what program you go to. If you go to a major aortic center, it is likely you will see enough pathology after 6 years to do pretty much everything under the 'CT' name. There are aortic super-fellowships out there at big centers for people who want to spend another year doing just aortic/aortic root surgery. They tend to be hired to a 1 year contract as junior faculty and help with attending call while they are learning from the other partners in the group. The lifestyle/pay is comparable, the primary difference is going to be in how your practice is setup, not whether you are focused on one pathology or not.
Something to keep in mind is that the endovascular revolution is on going. TAVR, TEVAR, zone 0 devices etc. are here to stay. Most CT surgeons do NOT have robust endovascular training and have little interest in developing them.