Why is everyone so obsessed with manufacturing and agri jobs when the majority of the population are employed by the service sector?

It's not just populists like Trump, everyone seems to be obsessed manufacturing jobs. Germany was literally paying Volkswagen to keep it's factories running. The German workforce consists of 44 million people. Volkswagen only employs around 600k people, and I am not sure how many of them are based in Germany. Everyone thinks China will dominate the world because they have the biggest manufacturing base, but even in China, less than 30 percent of the population work in manufacturing. In the United States in particular, 10 percent of the population are employed by the manufacturing sector, but all governments seemed to be obsessed with bringing back the jobs to America, while no one talks about the outsourcing that is happening in the service industry to places like India, which is putting much more people out of their jobs.

It's even worse for agriculture. The EU hasn't been able to pass the Mercesour trade deal, because French farmers were unhappy. The main thing that Trump wants to get in his trade deals is getting countries to buy more soybeans to please American farmers. Tariffs negotiations almost exclusively fail because of disagreements beef, fishing, soybeans, etc. All this while only 3.8 EU population are employed by the agriculture sector, 1.6 percent for the USA.

I get that populist politicians want to please their voters, but if farmers and factory workers make such a small share of the population, why do they matter so much? Like if you do something that makes beef cheaper, yes it will hurt farmers, but it will make restaurant meals cheaper, which means more employment in the hospitality industry, which employs way more people than the agriculture industry.

What am I missing here?