yes, it's not the sexiest online banking, but you can do everything you need to do, including setting up automated bill pay. my credit union has an app that allows me to do mobile deposit as well, so i almost never need to go to a branch. the credit card i also have with them shows basic account info, but uses a connected (i.e., single sign-on), but separate, website for setting up autopay and other services.

for getting cash, most credit unions are part of the co-op network for atms: https://co-opcreditunions.org/locator/ so you have similar availability to a major bank (but admittedly a little more obscured).

You're right that traditionally credit unions and community banks have used antiquated consumer facing tech (online banking, mobile banking, loan applications, online account opening, etc) owned by 1 of 3 OG financial technology companies in the U.S.: Fiserv, FIS, and Jack Henry. They are all multi-billion dollar public companies that have formed primarily via acquisitions.

I started a company to challenge the incumbents after running a credit union as CTO.

yes, i've indirectly dealt with both fiserv and jack henry on past consulting projects and they're definitely slow-moving dinosaurs. =)