Kaspersky's claims that Microsoft doesn't give them enough time to ensure their software is compatible doesn't really ring true for me, because between the Release Preview, Slow, and Fast rings, people can get their hands on Microsoft OS versions long in advance of Microsoft pushing them out to consumers.
Having a limit on the number of antivirus products a computer has makes sense, antivirus software often causes conflicts with other antivirus software, and a large amount of security software on a PC causes it to run very slowly, as duplicated scanning efforts take up a majority of drive performance on the slow 5400 rpm hard drives shipped with most consumer PCs today.
To be clear: Antivirus companies have acted like a plague on Windows computers for a long time. They use scare tactics to convince people to spend money on placebo-effect tools that rarely protect them from the type of malware they actually are likely to encounter.
One of the favored strategies is to bundle on new PCs with a short trial, and then tell people they won't be protected unless they subscribe. People aren't told that if they just remove the third party product that was preinstalled on their PC, they'll have perfectly serviceable antivirus.
That isn't to say Windows 10 doesn't have issues that still bother me, but let's just say that Kaspersky crying about them doesn't bother me much.