The dominance of Internet Explorer had longstanding negative effect on the web. Even today there’re industrial and internal banking applications that only run on IE, and nothing else. With Chromium being increasingly the only supported browser we soon won’t have a choice which browser to use for certain websites anymore (e.g. Firefox).
IE’s decline came to be because it was slow and didn’t progress for many years, unlike Firefox at the time. With Google being interested in the continued development of the web this won’t happen. Google pushes detrimental standards like “Web Environment Integrity API” today, they tried it with FLoC a while back. If Google succeeds in making the web more closed, another browser won’t have a chance to catch up.
At this point we have only 3 mostly feature complete browser engines (Chromium’s, Safari’s and Firefox’s). With Firefox declining it might soon only be 2 that work on all websites. It isn’t good for an open standar if there’re only few implementations.