There are all sorts of ideas that could work e.g. content (netflix/spotify), payments, insurance, smart speakers ...
I would recommend approaching this by thinking of a useful framework to categorise the particular tactics to be employed.
- Products / Services
- Markets (despite them saying B2C, take the initiative to also explore B2B or B2B2C; make your own assumption)
Thinking about telco-specific solutions, there was a big push over the past decade to convergence via bundling i.e. quad-play, triple-play. The idea being bundling increased customer stickiness and lifetime value. Although the jury is still out on whether this works, one option to present is bundling TV/OTT, fixed fibre and mobile.
Now, telcos are also pushing to capture more of their customer wallet through owning the home - smart home tech, bundling of non-telco services e.g. financial services and energy.
You may even want to think about how COVID/WFH could change the product mix e.g. cross selling network equipment (better routers/mesh), teleconferencing equipment, selling a signal booster if 4G/5G signal is poor in the house.