It is widely understood that when you multitask, you do many things poorly versus focusing on a single thing and doing it well. I believe it is just how we are built as human beings and especially how teams are built. Scrum teams should be able to focus on a single product at a time. If teams are allowed to do this, you get all the benefits of collaboration (teamwork) without the inherent loss of productivity in context switching between more than a single product in a sprint, or the loss of team work when team members are split up and thinking about and working on multiple products.
This is not Scrum.
I see too many teams faced with this situation today, Product Owners and organizations unable to truly prioritize between products, too afraid to say “no” or at least “not yet” to stakeholders or even customers. To be fair, it is often not the Product Owner I see at fault, it is the executive stakeholders who are unable or unwilling to prioritize between products and are instead committed to trying to keep everyone happy by being able to say that progress is being made when in actuality progress is being slowed across all products in favor of being able to say they are being worked on.
It takes some courage for executives to protect teams from this type of situation. It means someone will have to wait their turn, but it also means when it is their turn they will see rapid and competent progress, and they will get the team’s exclusive attention and the best of all minds working together on it.
When teams work on multiple products at the same time their productivity is eviscerated, and even if Scrum can be adapted to this situation, it does not mean it should be. Make people wait their turn or spin up more teams if you cannot wait. Don’t dilute the power that a focused team brings to product development, don’t hobble their productivity and creativity. Be brave and focus. You won’t regret it.