I don't see them as even "merely a necessary evil". Things would be very different without these companies, or if they were different than they are now.
I would probably love Apple if it was run by Woz, or followed in his footsteps. Although he is a very well known employee of Apple that is largely responsible for the company existing it probably would have been minor if it was run with his sensibilities, and would not likely still exist.
Microsoft is one of the main companies I blame for the current state of low software with quality issues that breaks standards, disregarding the importance of the user, sold at premium prices. Due to how well known it is in the market most people are scared to look elsewhere since they feel other options would be too difficult, not serve their purposes, or not work, even though all of these really apply equally to most of the options out there.
Just because Google hasn't done anything "bad" that you have noticed has a negative impact on your privacy or how you live doesn't mean they haven't. Or won't. They have done a few things I disagree with over the years, and it is on the other side of this argument. I feel that they should not restrict the results for searches based on copyright laws and such, and that everyone, in every country and at all times, should have access to all information that is supposedly available to the public. Of course, many want certain information to go away, which I disagree with for the most part, but brings up another important thing to consider about all of these companies.
Their users and customers are largely to blame for all the "evil" they do, not the companies themselves. Now governments more fully support companies like this, so politicians and lawmakers are also a good place to put blame. Then you have those that elected these people, or allow them to make such decisions, as well as those who ignore the problem, or those that make complaints but never actually DO anything. So, yeah, there are evil corporations, but they don't just appear with unlimited power, already having oppressed people. Those named here aren't alone, or the worst, and you don't have to like or dislike them.
I was going to go on, but I will just leave it there. There are other reasons to dislike these companies, which are included in my list of reasons against them, but I still use what they offer at times, in various ways. I vote with my money. (Also, bloatware and ads forced down your throat are unacceptable to me.)