[ewood]

In many cases it is not Bloomberg's monopoly but the data provider's. The licensing and royalty agreements between Bloomberg and the data provider have very onerous terms including restricting how many screens the data can be displayed on, what mediums the data can be transferred to, and where and for what purpose the data can be used. The terminal restrictions and API limitations that Bloomberg imposes are usually driven by these concerns.

Bloomberg offers less restrictive APIs but they are even more costly than a terminal license and often require the end user to sign agreements with the data providers directly and pay additional royalties.