Yeah I guess so, although bizarrely the land mass of Ireland is included under the British isles, the state of Ireland (the republic of Ireland) isn't.
Surely it should have been 'Team Great Britain, Isle of Man, and Channel Islands'. The powers that be probably figured there wasn't enough room to print that on competitors vests, so just went for 'Team GB'.
The full name of the team is "Team GB and Northern Ireland", shortened for convenience.
"British Isles" is a geographical term which has nothing to do with politics. The analogy is with "America", a continent that comprises the separate nations of Canada, USA and all those South American countries. Thus, Ireland can no more claim to be outside the British Isles than Brazil (say) can claim to be outside America.