For me it is only Excel. I am not even a power user, but its strongest features is its integration with powerquery. In many use cases it is perfectly enough to

For me it is only Excel. I am not even a power user, but its strongest features is its integration with powerquery. In many use cases it is perfectly enough to quickly analyze some data and it is still friendly enough to give non-tech workers possibilities to refresh the newest data available. Apart from that every other part of the MS ecosystem is replaceable. If there would be a solution for corporate IT account management, Windows could be replaced without much friction.