Brit here. We (the household) had our landline switched over from analog to digital last year so if our internet connection drops out we won’t be able to use the landline. the reasoning was the phone cables are getting old and the government doesn’t want to spend money to replace them so landlines just connect to the router now. i know landlines aren’t obsolete but the technology which made them redundant is, at least in my area. the rollover is expected to be completed by 2027 iirc