Satellite is was using Bell's channel line up. MLB is not available on Optik at present.
You could voice your support on the existing idea: https://forum.telus.com/t5/Ideas/Sports-Channels-Add-MLB-Network/idi-p/46921 .
I posted this in the thread Nighthawk linked to but I'll paste it here again for visibility.
MLB Network will most likely not be coming to Telus or any other new providers in Canada in the foreseeable future. DAZN recently signed a 3 year deal with the network which will prevent other providers from picking it up. DAZN has been very aggressive in acquiring sports broadcasting rights over the last couple years and it's starting to really hurt Canadian consumers who want to view some sports content on their existing TV product and not have to pay for an additional service.