I don't think size is really relevant to the issue at all, it's simply the general anti-competitive practises that size has enabled these companies to pursue as

I don't think size is really relevant to the issue at all, it's simply the general anti-competitive practises that size has enabled these companies to pursue as aggressively as needed to crush all competition. What Microsoft is doing with bundling for example is far more destructive to competition than acquisitions. I think what we need is more nuanced regulation to give smaller competitors room to compete with big tech products, if this were the case then who cares about their size or acquisitions? So long as smaller competitors can always rise and challenge the big players then size is fine since it would just correlate to quality and value, rather than an ability and willingness to crush competition. The question to be asking is if a practise is unduly restricting competition. Having a market share of 95% is fine in my eyes so long as there is competition.