I wish it were that simple, sometimes. Not everybody is in a position to, for varying reasons. We’re privileged to have that ability. There are entire groups of people who just can’t because of being “black listed” for one reason or another.
Initially this works, but unfortunately trends in society are making your options shrink over time.
I switched from the cheapest telco around (by a significant margin at the time, $10–25/month instead of $35–50 for what I needed), circles.life, in part because they had no website to control things, view usage, &c., but only exposed that stuff through a mobile app that I couldn’t run. (Also very clearly illegal conduct in matters like sending spam text messages from their service notifications number, which they refused to even acknowledge when directly confronted.) But the telco I’m on now, amaysim, introduced some new roaming arrangement a few months ago that you can only activate through their app, not their website. (I would like to use it next month, so hopefully talking to customer support will work. At least they actually let you talk to support without using their app, which circles.life made hard.) Also their website is painfully slow to log in: from hitting the login button to the next page starting to load takes fully 48 seconds, and their site is of the idiotic “insist on logging you out after ten minutes” variety (like most of these sorts of businesses, for baffling reasons), so viewing my usage is fairly painful. At least I can keep the tab open at the usage page, and then when I reload and get presented with the login form and press the login button, it’ll end up back at the usage page in a minute or so; some will lose what page you were on, so that you have to go through multiple steps each time.
Banks, most of the biggest ones in Australia still have online banking, but it’s generally painful to log into and use compared to their mobile apps, and they all have a nasty habit of adding new stuff to mobile either first or only. And newer bank labels are commonly mobile-only. Internet banking is largely treated as a legacy matter which they’re all just not particularly interested in.