[janfromdaito]

SIM banks used to be a thing, but they get less common and common every year.

Why they are dying out? Because they are not that easy to source, maintain, scale or achieve super high reliability with them. Also, hard to offer a high availability option when the phone network only (well, in most cases) accepts one device per phone number.

Edito: Additionally, important to note is that most SIM cards can only be used for a prolonged time in that providers phone network. You e.g. can not buy US SIMS, ship them to the EU and host them there. T-Mobile US (and others) cut you off after (usually) 2 months of roaming.

[noAnswer]

> Also, hard to offer a high availability option when the phone network only (well, in most cases) accepts one device per phone number.

1. I guess it depends on your providers/region. From all three German mobile network providers (Telekom, Vodafone, o2) you can get up to three SIM-Cards for the same number.

2. The VoIP provider Sipgate (sorry again German) gives you as much SIM-Cards and eSIMs as you like (In exchange for money of course). You can route mobile as well as land line numbers to a VoIP-Phone, -Client or mobile phones. They can all ring in parallel.

3. Many years ago, I saw a presentation on a CCC event. (Sadly I can't find a video of it just now.) It was from a guy who documented how he became a mobile provider. He wasn't just reselling, because his numbers terminated in his own Asterisk server! So maybe, people looking for the best solution, should look into how to become a virtual mobile provider.

[Scoundreller]

I suspect they’re still used for outbound scam calls/texts (and maybe inbound too), and probably gray-market voip-pstn interfaces in countries that make int’l voip interchange expensive.

Some cool stuff on aliexpress with 128 SIM card slots and 8 or 16 gsm radios where you can program your choice of imei.

As a Canadian with crappy cellular coverage, I’ve dreamt of having a couple French SIM cards that I could mail to France every so often so it looked while I wasn’t 100% roaming just to have a cheap unlimited data plan with cheaper int’l calling.

[yencabulator]

Meanwhile, eSIM has come into existence, and removes the annoyance of dealing with the physical SIM card.