Fujifilm X100T has a 16.0MP APS-C (23.6 x 15.8 mm ) sized CMOS sensor and features EXR Processor II processor. On the other hand, Sony RX100 IV has a 20.0MP 1" (13.2 x 8.8 mm ) sized BSI-CMOS sensor and features Bionz X processor.
Below you can see the X100T and RX100 IV sensor size comparison.
As seen above, Fujifilm X100T has a 3.2x Larger sensor area than Sony RX100 IV. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.