|I feel you pain, having had to "fix" a site which only broke on IE6, many moons ago.
The sad part is that the engine Microsoft put in the original Edge was actually rather good -- whilst the version of IE at the time shared the same engine, they had a bunch of flags to make IE compatible with all the bugs in the past, which people had built internal software on. Microsoft has this constant tension between trying to keep as much backwards compatibility as possible and fixing stuff that's clearly broken: their official stance is to try to keep things alive and compatible as long as possible, since it's in the interests of their users (and, ultimately, themselves) that things continue to "Just Work". Windows is a great example: you can still run Win3.1 executables on it!
Sadly, they can never please everyone: for every person who is mad about, eg IE being rubbish, there are a bunch of corporates using some old system that requires the brokenness that's in IE ):
They only gave up on their own engines (Trident and Chakra) because it made more business sense to hitch their carts to an existing rendering & JS engine that has someone else spending time (read: money) on it, so they chose Chromium's renderer, but honestly have ripped out all the Chrome bs. Whilst I'm a Firefox person, I'd take Edge in a heartbeat over Chrome / Chromium / Brave. Microsoft has done a lot of turnaround since Ballmer left and Satya Nadella took the helm.
For the user, the loss of Trident and Chakra (the modern versions, which were, I re-iterate, Rather Good) is a bad thing: there are essentially only two contenders in the renderer space now: Chromium and Firefox. One could argue a case for Safari's webkit, I guess. Anyway, it means that we're edging closer to another "IE situation" where a dominant browser can start implementing things that aren't standards or implementing standards incorrectly and people assume that when it doesn't work on another browser, that other browser must be broken. Google has already taken quite a few stabs at this stance (Polymer / WebComponents being a good example: when they shifted YouTube to use WebComponents, which were non-standard, but natively supported by Chrome, all non-Chrome users got a rubbish YouTube experience and, naturally, blamed their browser).
On the spying front: there are free products (truly free), but they're scarce (all the software that I release for free is truly free, for example, not that I'm releasing browsers or anything useful like that!).
Mozilla does allow you to opt out of basically everything from the options page. I say "basically everything" because, eg, things like addon installs are still tracked (so you can rate & others can see install counts on the addons page). If I had to rank browsers based on how they respect the user, I'd definitely start with Firefox and then Edge. But to each their own. I don't expect to be a dark entity on the web, but if I can make the lives of the zuck-fairies a little harder, I'm all for it.
If you say that getting the money
is the most important thing
You will spend your life
completely wasting your time
You will be doing things
you don't like doing
In order to go on living
That is, to go on doing things
you don't like doing
Which is stupid.