Not quite. What you're looking at is availability in terms of fare buckets, NOT in terms of seats. These are two different things.

The number under each fare bucket indicates the number of reservations that the airline is willing to take. It has little relevance to the number of seats available.

The values depend on the point of sale chosen for the search, and the route. For example if you search for availability for KWI-DXB-MNL on EK, you might find J0C0I0O0 on the DXB-MNL flight, but if you search DXB-MNL alone you might see J4C4I4O4. Similarly, if you change the point of sale from USA to UK you might see different results.

In my example, we can't tell from the KWI-DXB-MNL search result that the DXB-MNL flight is fully booked because EK is willing to take bookings out of DXB (and possibly from other markets) in business. We can only say that EK is not taking bookings on that particular flight/connection.

Another example: MEL-DXB-LHR, might see zeroed out in economy on MEL-DXB sector under this search, but turns to fully open when searching for MEL-DXB alone.

Hope this clarifies things a little.