The problem is — or, at least, from my perspective as an old school/pre-WWW computer user — that a lot of sites aren't made for mobile. If they are, it's great, it's fine, the app might offer a couple bonuses, but you should have a good experience just using a browser. If they aren't — the app is a must.
Forums are a great example of this. When Android and iOS were new, most forums ran like shit in a mobile browser, and if you had a lot to type, you'd often lose it if you didn't remember to copy it to the clipboard first. Even then, with RAM limitations, you could lose your work. An app was created called Tapatalk, it did require forum owners to install a plugin on their end, but it made forums into an app, and it was good — until they got greedy. Tapatalk was a good way to bypass the ads on the forum ("because phone screens are smaller"). Then Tapatalk started putting their own ads in. They were taking money from the forum operators, not giving them any back, and making money on the whole process. Forums stopped installing the plugin, and many that had it began removing it.
Around the same time, forum software makers, like Invision, phpBB, and vBulletin, began including mobile support natively, so if a forum updated their software, they got mobile support. Thus, the Tapatalk gravy train came to a screeching halt. They'd pissed off forum users and forum owners, and now neither of them needed Tapatalk.
These days, I think most sites are made with mobile in mind. But apps can scrape more data without permission, so they tend to be favoured by the people who run the sites, especially concerning Android users, who can natively run Firefox and uBlock Origin. But they also love Android users who love Chrome, and iOS users in total, because they can get more by those users (generally, a majority of them at least).