I think you are completely wrong, let me make the argument. As a whole, H2 cars are also quite heavy. You literally require everything that is in an EV plus multiple extra subsystems that are incredibly complex and not light by any means. The manufacturing and materials are very both complex and expensive.
You need the fuel cell itself, and that is not just some thin layer, but a whole complex subsystem that requires all kind of system around it. Then you need a very heavy high pressure tank and a high pressure fuel system. Looking at H2 cars and the amount of parts these system adds is illuminating.
Next up, you can make a battery completely structural, meaning the battery actually serves the function that the steel frame used to serve in a car. Integrated like that, the battery weight is almost negative.
Battery technology is improving fast, with both cost going down and energy and power density going up year over year. H2 cars can not compete in the current environment and there are no projection that they ever can.
Pretty much everybody has now given up on H2 cars ever being remotely viable. Some people are still holding on to the hope for H2 in trucking, but some large truck companies have already dropped it, and with Tesla Semi going into mass production, people will realize that H2 trucking has no future as they have realized it with cars.
You also seem to ignore all the negatives of H2. Fuel station that are about 100-1000x more expensive per station, and you need more of them. You can't charge over night at home with energy that is largely already available. Even if EU government funded H2 is successful, that would still not be enough for all of transportation, not even close.
The majority of hydrogen for the foreseeable future will by methane based and when the grid will already be almost totally carbon free, much of hydrogen on the planet will still not be carbon free.
And if you are talking 'in 10 years' you need to also look forward to what batteries will be like in 10 years. In 10 years its possible that we could have lithium sulphur batteries. Such batteries would be incredibly cheap and have crazy high energy density. Battery that cost a few 100$ and fits in a glove box could give multiple 100 miles to a small car. That is just one possible battery tech that might be viable in 10 years.
Last, let me address your point about mining. While of course the extra subsystems for H2 also need materials, a much bigger issue you have ignored. A FCEV is inherently significantly less efficient, this means that even if you are producing all the H2 with solar and win, the total amount of solar and wind required would mean you would need a significant amount more solar and wind. Guess what that requires, significantly more mining, more solar panels covering more nature, more wind turbines everywhere (that people already hate).
I really don't understand people love for these hydrogen fuel cell vehicles.