LUTs are still the building block of all FPGAs. Logic elements are just a higher level of hierarchy. For example, according to the Intel Arria 10 handbook, an

LUTs are still the building block of all FPGAs. Logic elements are just a higher level of hierarchy. For example, according to the Intel Arria 10 handbook, an ALM contains 2 4-input LUTs and 4 3-input LUTs, which can be combined in various ways. (See figure 7 of the A10 handbook.)