People seem to assume that the "big tech companies" have good security, and the "small players" do not.
That's too broad a stroke to brush, here's a quick counterpoint:
For many people who purchase a new Windows 10 PC, Microsoft's built-in Edge browser has one purpose: to download an alternate browser like Google Chrome. The most common way to do this for people who don't have the URL memorized? Type "download Chrome" in the address bar and click the first result provided by Bing search. Unfortunately those unsuspecting users have a high chance of downloading malware and adware.
Computer security is complex enough where there is no easy way to predict who has good security. I would hypothesize that the ratio of service-or-system complexity vs. available resources is a better predictor.
I haven't looked into the broader topic of malware via Bing searches, for the purposes of this article, lets assume the malware download is "in product" with the more proficient hacker groups.
Does this mean we should start worrying about who else is embedding their web content into somebody's site? Yeah.
And if it does, then is broader web becoming unsafe, the same way web shopping on small sites used to be?
Should you stop using sites with a heavy ad services, like evite?