The timescale is not meant to be realistic. This is a core basic design philosophy of the series and it's never going to be changed- they would have to update literally everything in the game to make sense for it. To make sims have more time to eat, you need to slow the time scale down, then slow the speed of the eating interaction, then slow how much hunger it refills in real time, then adjust literally everything else on and on and on...is the game still fun if days are twice as long and therefore it takes twice as long in real time to sleep? Is it still fun if days are twice as long and skills still raise at the same rate, or do you slow those down too? And if they're slowed down, too, does it start to drag? The time scale is very carefully calibrated and intentionally not even close to 1:1. Eating takes a while because the only option you have is to make time take longer- which comes with the above problems- or make animations faster, which looks bad and senseless.
If you made a shower only 6-10 minutes, Sims would literally step into it, clean for under 10 real world seconds, and step out. And the game would become imbalanced, because 6-10 minutes of a Sim's day spent raising their hygiene motive means the motive is basically pointless- you never have to concern yourself with it if it goes that fast. At the end of the day this is a video game and hardship and overcoming it and rules and progression are what makes it a game and not a sandbox toy, so they won't be changing things like that any time soon.
Traditionally, that's the feedback loop that keeps the game engaging- it's all about snowballing things into more effective usage of time, to "earn" that free time and make the most of what limited time your Sims are given. You make more money with better skills which affords you better furniture and faster production of food and better sleep and easier cleaning, and those things compound to give you more time to make more skills and make more money and make more friends, which further compounds to make all those things faster, and faster, and faster- until you have so little reason to do anything for "productivity" reasons that it can get boring to do anything at all, because it's just "for fun".
Recently I've been playing with aging turned entirely off. It makes every single thing you do less stressful- I don't have to worry about what 3 sims are going to do on monday and making sure all 3 are getting things done. I can play as one, and leave the other two alone- because it doesn't "lose time" to do that anymore. Turning aging off will probably help if you feel rushed.
If you're on PC, I actually made a mod specifically to facilitate "rotational" play in one household- you're prompted each day to choose which sims age up, and can choose nobody if you want- or choose to only age sims you felt "got the most out of the day". You can play one sim each day and only age them up that day- then do someone elses day tomorrow. Then if you're having a fun holiday party, you can age nobody up- and no time is "wasted" because no hard progression happens, you just let it ride. (I also have a mod that makes holidays easier to handle by slowing motive decay on them as a holiday tradition.)
This gameplay loop is what makes the series engaging IMO but if you want it more relaxed these are pretty good options. I don't really prefer aging entirely off, and I like the challenge of having limited time, but having to prioritize who gets attention bugs me, so I made these!