They aren't really providing a service, but they're getting between confused people and public services
Consumer finance journalists complain a lot about their sites appearing before the real thing in search results
"You need this sign in your break room else you'll be fined $10,000! Just subscribe for $299/year and we'll mail you labor posters each year." These can be found for like $10 and don't change yearly.
"This form needs to be filed else you'll be fined! Pay us $499 and we'll take care of it!" Free to file online.
Even forming a business in my state is like 2 forms and $125 and can be done all online. But if you were to google how to, you'd find all these people to "Help out" and it'd end up costing you $1000-2000 for their "Help".
I always tell people to expect a minimum of $1k/yr to maintain a business and that’s to pay for a registered agent, a virtual office, and a domain and website (I also recommend a CPA). A registered agent exists only to forward legal correspondence directly to the owner. A virtual office handles all of the mail (which includes the junk mail you mention but can be silently processed out using their virtual mailbox service). And a website to provide an easy means of communication (again with spam filters in place)
I never see junk mail and I have started 5 successful businesses over the past 20 years. Spam phone calls is a completely separate unsolved problem, however
The worse practice IMO is exploiting a captive audience. It doesn't matter how stupid you are if you're an Apple developer or an Oracle customer; these companies will bleed you dry for simply touching their product. The only path of recourse is antitrust settlement, which is a lengthy and unnecessary process that is inherently stacked in the favor of whoever can hire more lawyers. Because of this, companies have no motivation to improve a paid product. Instead, the goal is to make you reliant on it somehow and then increase the price. We see this in Netflix, Amazon Prime, Windows/Office365/OneDrive, Apple developer program/Apple One/iCloud/App Store, and YouTube's TV/subscription services. The most successful businesses in our daily lives are the ones that have dug their claws into us and refuse to be anything other than a parasite.
I'd like to distinguish between those that bring services closer to customers and those that hinder customers getting to the services they intend to use
When I'm searching for in for that the ultimate answer is coming from a government entity, usually it's because I want authoritative information, and I'm not willing to rely on a third party hopefully getting it right.
The only thing I want from Google when making these searches is to deep link me into the appropriate section of the official site. The only reason I'll visit a third party site is if I don't have a good official link and I'm hoping to get a clue to refine my search by reading specific laws or statute id's they might reference, since I'm not going to make tax filing decisions or assume directions given regarding a DMV process are correct from some random online website.
Dodgy site that appears so correct you enter your private info < legit gov portal.
True even if gov site could be better designed.
Then we need to fix that problem, not make it OK for it to exist. A government site should be the source of truth on information about governmental affairs, or relevant to this article, if I search for "$STATE DMV", I should end up there first. If I search "how do I register my car in $STATE", that answer should also come from a governmental site.