I’m not a staunch Labour supporter let alone a member, and even I can see that not voting strategically each and every time there’s an election just gives more power to the Tories. I’m in a marginal and I voted Labour in the last election regardless of what I thought of Corbyn.
There comes a point when you're essentially voting for the red team out of tribalism. Labour really need something better than being slightly less shit than the blue team*
*Although I'd argue that doesn't really apply anymore, with Starmer trying to outflank the Tories on the right.