I think the more crucial thing here is that children do not need you to be perfect and make near perfect decisions and offer near perfect input all the time.
Most people put on the television for their children because they need a break. I totally agree that no baby needs that much stimulation but to be honest, I think we underestimate typical children's ability to self-select what's best for them to attend to in the environment.
A 5 month old isn't going to have the attention span to attend to 90 minutes of television, whether broken up or not. So while "watching television", they will also be looking at the lights, tracking you moving across the room, playing with their fingers, looking at the carpet etc. They are not going to be glued to the television. I've seen family members who have those Baby Einstein things etc and their babies don't sit transfixed. They tune in and tune out of that stimulus as they do with everything else.
I think to be honest it's a bigger issue when they're older and it can become addictive. When I was unwell with depression my 3 year old son got a lot more television than I would have chosen in my right state of mind and I could see the hook it had on him, even though he was doing other things: having time with me colouring/baking/going out/playing duplo/going out on his bikes. Yet I'm not going to beat myself up about having been where I was - I didn't choose it and when I was well we took steps to change it.
Everything in life is about balance. You're going to do certain things as a parent out of a need for your own space and that's not a sin or a travesty because actually self-care is a crucial factor in mental well-being and allowing you to be present and fully attuned the rest of the day. Kids used to be allowed wail in a playpen for hours, we don't do that now. At one point in history babies were put up on pegs! Every generation will have its "not great but not abusive" type of non-human "babysitter".
One of the hardest things about being a mother these days is the endless and relentless critical analysis of every single decision. This isn't mentally healthy and is its own suffering and detraction from being the mother you want to be. I wonder do people hear themselves when they start the Monty Python Yorkshiremen sketch: "well I had 7 under 5 and no husband and no money and severe depression and cancer and a disability and I managed to be a better mother than you by never putting on half an hour of television". Bully for you, lovies. Yours is the harder path, I see.. but my life is happening to me as Larkin said.
We're not mothers in Auschwitz or in the dumps of Brazil, it's true.. but that doesn't mean that we have to be self-flagellating every time we make a decision that wouldn't be made by The Perfect Mother. It's only a bit of television in a warm and loving stimulating environment with plenty of cuddles, kisses, naps and good food and an interested and loving mother. Honestly. It isn't heroin in the baby bottle.