Quite the opposite, there are several good reasons to do it. Take a look to this article (I don't fully agree with all of it, but you'll get the gist of it)
They are important for several reasons, most importantly because they
allow designers to compress content on the home page. By compressing
content, you fit more content in less space. This means that readers
can scan headlines more quickly and that you can fit more information
above the fold.
Also, “Read more” links allow website administrators to more easily
track the most popular content. Designers who put entire articles on
the home page may make it difficult for website administrators to
track the most popular articles and understand what users want to see.
The third and probably most practical reason for having “Read more”
links on a website is money. Websites that monetize traffic understand
that the more their readers click on links, the more likely they will
look at and click on advertisements. “Read more” links can double or
even triple the number of page views a website receives, making it
more attractive to advertisers.
As per your remark
Making someone tap a button to continue browsing your site seems like
a good way to lose their interest
you should take a look at this reading about UX myths.
Finally, the word "more" is really powerful in several aspects, basically you're telling your users they will get a bigger amount of something good (if they choose to read the article) or if ignored, you know the user won't want more of that. Either way, you can track and measure user expectation VS site owner expectation and adjust accordingly