Most people have a fixed amount of disposable income each month.
That has to mean that if we raise prices by means of tariffs or other methods, people only have one option: buy less stuff each month.
It is not immediately clear to me how this benefits anybody.
This is of course a very simplified economic "model" here. Things are just a tiny bit more complex.
There's a fine line between regulating economy and making it worse for everyone. But without any form of regulation, you're almost certain the system ends up going bonkers.
Tariffs are one way of regulating worldwide economy, and disposing of them altogether is probably not a good idea.
One thing (among many others) you're overlooking in this little "analysis" is that you're assuming that tariffs (and other means) make no difference to the economy, except higher prices for the consumer. This of course can't be true - if not excessive, it can actually improve things, and people would have more money to spend. Prices alone mean nothing if you don't link them to the standard of living of a given population.
The mere idea that lower prices for goods would lead to people getting richer somehow is completely silly. Doesn't work this way - or it's only very temporary. If you keep dragging prices down, everyone ends up poorer in the end. When you don't actively regulate economy, it just ends up regulating itself. And if everything gets cheaper, wages will mechanically drop too, eventually.
If you think we can just keep getting cheap goods from China (for instance) forever without it impacting our wealth negatively, IMHO you're largely deluded. At best, it would just end up making money have less value, without changing anything much to the overall standard of living. At worst, it would end up making us all poorer because it's just not sustainable as such.