To collect the data, use string concatenation, flatten() and split() in an array formula. To aggregate and pivot the data, use query() with a pivot clause, like this:

=arrayformula( 
  query( 
    split( flatten(E4:N & "→" & E3:N3), "→", false, false), 
    "select Col1, count(Col1) 
     where Col1 is not null 
     group by Col1 
     pivot Col2", 
    0 
  ) 
)

See query(), split() and flatten().

To collect the data, use string concatenation, flatten() and split() in an array formula. To aggregate and pivot the data, use query() with a pivot clause, like this:

=arrayformula( 
  query( 
    split( flatten(E4:N & "→" & E3:N3), "→", false, false), 
    "select Col1, count(Col1) 
     where Col1 is not null 
     group by Col1 
     pivot Col2", 
    0 
  ) 
)

The formula above is an array formula that will create the whole result table, complete with headers, in one go.

The results look like this:

See query(), split() and flatten().