I remember when Microsoft got in trouble for bundling a web browser with the OS.

Sure, they have no obligation but the way you describe Newpipe to paint it as "obstructive" feels off to me.

When you offer a free service, by definition of it being free, you can't hold consumers of that service accountable for not furthering your revenue. They are impeding revenue only if it's not actually free (or only under false pretenses) which dismantles your first sentence here.