Emails sent from white house accounts are recorded and saved by the government, so nothing too wrong about it, legally.
The optics are bad because of what Clinton did, but there is a huge difference. Clinton exclusively used a server out of the sight and control and protection of government agencies responsible for those things. The Trump officials use government servers and accounts for government business. They're also clearly making best effort to obey the Records Act, which Clinton did not do.
I can see it is reasonable to forward your travel itinerary to a personal account so you can access it on the road. If you have to access it from government servers, you'd have to go to a secure location and use secure machines. Hard to do that if you're in line at the airport.
At the very least, they should provide full disclosure of every email on these servers for public scrutiny.
It would be important to know they're not conducting Trump business (like Clinton did with her "charity"), or doing quid pro quo favors (as Clinton did).
Another difference is Clinton was a career politician and a lawyer. She had to know better. You can't say the same about Trump or his family.