I would say for personal stuff (ie, non-programming) it is. For programming, I continually have to switch back to google. DDG is way worse for me. Maybe it's just me, but the types of things I search for just don't work on DDG and I've wasted way too much of my time looking for answers using DDG, only to find them quickly with Google. It totally frustrates me, because I would much rather use DDG.
Critical operators like "site:" are not available in DDG.
The user pays for Google in the end, just not consensually. It's a closed loop. All the money ultimately comes from the users. Product or politics, all advertisers are expecting to get some return.
Unfortunately it's in human nature to not want to pay. Search needs to be a utility that we all fund to make it the best tool for society.
All the money comes from some of the users. Sure Google is collecting everyone's data, but in the end the vast majority of it is worthless. I'd be surprised if even 1% of users are profitable for the ecosystem. The tiny minority clicking on ads and buying products is subsidizing everyone else.
So I have to recoup that cost. I pass that cost onto all of my customers by mixing it into the cost of goods and services. If you buy things from me, even if you are not a subscriber to google/yahoo, you have in effect paid for those services. This is somewhat invisible to the people with those email addresses but does actually affect them, if only a little bit.
Google would tell you that you can simply start with a low volume and ramp up slowly. In reality this is simply not practical for most businesses. This gets into discussions around queue-per-domain management and rate-limit-per-domain, but quickly falls apart when you have to notify a large number of your customers on a time sensitive transaction that is out-of-band from their web browsing experience. A modern work around is to have a cell phone application for notifications rather than email assuming you let your own customers choose that over smtp in their profile. Another work around is to use an email campaign provider that already pays into the whitelists, but then I have to give your email address to a potentially shady company that may cross-sell / cross-market to you.
However, assuming you’re willing to pay for privacy, switching e-mail is super easy. For example, from the Fastmail UI, you literally log in to your Google account and all your mail is transferred to Fastmail.
Switching to DDG? It’s 95% as good.
Switching to Apple Maps or OSM? It’s 95% as good.
Google Drive? There are 100 competitors.
There is one site you cannot do without, and that is YouTube. Everything else from Google can easily be ditched, the only two things in your way could be a reluctance to pay money and a slight feeling of unease at having to get used to something else.