VOIP providers that provide support to receiving SMS from short codes?

Voip.ms does and did since at least 2017, as the [Voip.ms] Received SMS message from short code number forum thread attests -- if you read the thread, the receiver also sent one, too. The announcement [Anveo] Support for Short Code SMS/Texting in USA is now live is from 2014. These are the two large VoIP SMS providers and they both do.

A powerful alternative could be the glocalme simbox which is a home gateway from the Internet to as many as four SIM cards. Your phone needs a data connection (so I feel the "No Extra Charge for Making and Receiving Calls while Roaming" blurb is misleading -- well glocalme doesn't charge anything but this device doesn't solve the expensive roaming problems) but it just so happens glocalme also sells global data solutions, various phone and portables hotspots.

Disclaimers: I am not affiliated with any of these, I have an Anveo subscription and a glocalme u2.

I happen to work for a full-blown multi-national phone operator.

Yes, there are VOIP providers supporting it.

There are many factors involved in getting this to work. VOIP providers are usually tiny players in the telecom industry and hence they usually buy telecom access from one big local operator. This means that they are limited by the bigger operator.

The intermediate operator (bigger) usually has very old and in-flexible systems and this could mean that many things aren't available for the smaller ones.

Then to the systems of the VOIP operators - since you say "VOIP" it could mean just SIP trunking. There are no text messages in SIP. One could have a software transform the texts into voice and the call the recipient but this is an investment some doesn't want to make.

There's no set of standards to do voice+text, one has to do them separately. Doing text messages isn't fun to do with the larger operators - they usually bluntly refuse to use modern standards. This makes it non-fun to integrate text messaging with them. You need a top-of-the-line developer or one with a lot of luck.

For doing short codes you usually need some kind of direct access to the local telecom ecosystem, it could be either direct or through an international telecom provider. This limits the numbers of VOIP providers you can choose from. Short codes aren't (normally) routed internationally.

Fact is that you could keep your number with your current VOIP provider and have text messages routed to another operator which is specialized in text messages. This however requires contact with people like me which is pretty much impossible.

So you need one that can do both voice and text. Lucky for you Canada is just next to the US so you should have a pretty large selection of competitors in this market. As mentioned Google Voice is one.