Is lifeweaver justified if your tank keeps getting walled off?

Hello, masters support here. I generally avoid playing lifeweaver and mercy at all costs, since i don't like their playstyle and i find that they're not that effective. Today i had a game in antartic peninsula in which we had a tank who ended up dying 9 times in 5 minutes, and we lost. He tried to play winston orisa and hog, and our dps comp was pharah ashe. I tried to coordinate our dps to shoot the middle pillar, but they didn't listen. So, i considered playing lifeweaver for the sole purpose of pulling him, but i decided to play ana and kiri instead. We obviously lost and this got me thinking if lifeweaver was a good pick against a demon mei.