I’m pretty sure that Fusio is a bit less dense. Optima seems like a variation on UA’s Polaris, and at its debut Polaris was touted as more dense than the traditional herringbone seat, which was previously viewed as the most dense flatbed J seat type.

As an example, AF gets 34 Optima seats between doors 1 and 2 in their A359. Some AF A359s have regular herringbone and there are only 32 seats in the same space.

Meanwhile, DL gets 32 Delta One suites into the similar space on its A359s (and actually uses extra space in the center rows that seem to be taken from galley monument space, with the same monuments as AF, they might only have 28 seats). Those I believe are Vantage XL seats by Thompson Aero which seem more like the Fusio.

Moreover, ANA gets 40 Fusio/Room suites between doors 2 and 3 of their 77W whereas UA gets 32 Polaris seats plus 32 Premium Plus seats in the same space (looking at AeroLOPA, if they went full Polaris in that section they might be able to get in 48).

BR gets 16 Royal Laurel herringbone seats plus 56 Premium Economy seats in the same space on their 77Ws (looking at AeroLOPA with existing lav arrangement, if they went full RL they would get 40 seats; if they moved the lavs to match the arrangement of ANA they would get 44 seats).