"The plane can hold 200 passengers."
"The plane holds 200 passengers."

"The plane can carry 200 passengers."
"The plane carries 200 passengers."

How necessary is "can", if the capacity of the plane is being talked about?
It's not necessary at all.
If you're talking about capacity:

The plane holds 200 passengers.
The plane can hold 200 passengers.
The plane carries 200 passengers.
The plane can carry 200 passengers.

If you're talking about current occupation:

The plane is [currently] holding 47 passengers.
The plane is [currently] carrying 47 passengers. (natural)
The plane currently holds 47 passengers. (natural-ish)
The plane currently carries 47 passengers.

Words in [brackets] can be omitted if desired.
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So, "hold" and "carry" mean "has enough room for X number of passengers", besides currently "having X number of passengers". Could there be ambiguities as to which meaning is intended?
 CSnyder's reply was promoted to an answer.
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