It's all a matter of the trade-offs and the costs of the benefit. Perhaps it's possible to reach a 100% clean electricity grid, but it would be extremely expensive to do so, and you'd certainly have more intermittency and less reliability if you did so.
While we all want net zero by 2050, I think there are many cheaper ways to do it than the last couple of percentage points on what is already a very clean electricity grid. Focusing on getting to 100%, when 92% or 93% might allow us to have and maintain the reliability and the affordability and sustainably is what I object to.