Also adding to this, it is really hard now to list down each and every feature because D365 has been growing day by day
You need to look from two perspective
1. Technical: It is completely changes and managed very differently through LCS with help of Microsoft
2. Functional: D365 has almost everything what AX 2012 has on top of that it has major highlights
1. User interface
2. Data management is way easier then AX 2012
3. Integration with other MS apps e.g. Azure, Power platform etc...
4. Additional modules: Landed cost, subscription billing, Automation features (Invoice, payment, collection etc...)
5. Power BI embedded in D365
Lot more
