The East India Trading company and Purdue Pharmaceuticals make for a more fair comparison.

They both killed more than an order of magnitude more people than the Tiananmen Square (and related) massacres.

One actually had a standing army for this purpose. The other is hiring.

Those examples aren't entirely invalid, but in one case of one of them (Purdue) they are facing legal jeopardy for their actions including a $270MM settlement in Oklahoma alone. The other company was founded 400 years ago, relied on letters of marque issued by (you guessed it) governments, and is no longer a going concern.

The thing about governments is that they have basically zero accountability to anyone except a better-armed government. We talk a good game here in the US, but it's certainly playing out differently.