For Apple specifically, I'm not sure which products you're referring to, but Apple does wield a lot of monopolistic power. And maybe some acquisitions there made sense, but there could have been alternative paths (for instance, maybe if some of those companies had stayed independent, they would have been integrated into Apple as well as other manufacturers via a different business model, like licensing, being part of the supply chain, etc). In general, a viable product should lead to a viable business, since the company making the product should be able to capture the value it's delivering... but yes, there are some exceptions where you need products to be really tightly integrated and acquisitions make sense. In fact, I'd argue that with _less_ M&A we'd be more likely to live in a world where (viable product) == (viable company), because the market would be more efficient.
Anyway, my argument for more regulatory oversight doesn't depend on ALL acquisitions being bad, so finding evidence that some were good for consumers doesn't necessarily negate it.
I feel like what we would end up disagreeing on though is whether we can trust regulatory oversight to do a good job of making that decision. I don't trust regulation in general, but in this case specifically, I'd trust it more than giving large companies free reign.