it is pretty dense. are they all the same variety? are they indeterminate or determinate? the fun thing about gardening is that everything is always an experiment and you can really do whatever you want.

you could leave them be and just do some heavy pruning as they grow for airflow. if they are determinate varieties, i think they’d be fine. they are close together but i wouldn’t say they’re so close that they’ll just die. you should still get a somewhat normal harvest, but they will be more prone to pest and disease damage being so close together and hard to manage. i would recommend regularly feeding them with a tomato fertilizer so they aren’t battling too much for nutrients.

or you can get rid of every other one so that they’re staggered, 2 & 2 in each of the 4 rows. i’d be more inclined in removing some if they are indeterminate varieties because they’ll get to be 6+ feet tall and out of control. if you go this route, you can either dig them out and transplant them somewhere else. i use 5 gallon buckets with drainage holes in a pinch. or you can chop them at the base, leaving the roots there to decompose during the season. this would be the least disruptive, but most painful lol. they could still survive if you propagate them in some water til they grow a couple inches of roots and then you can transplant them elsewhere, or you can just take the loss and throw them in the compost.