Source on these claims? Leather production isn't exactly easy on the environment, nor the health of (typically third-world country) workers involved in the process.
Personally I've been wearing the same pair of synthetic leather boots to my job which has me walk ~20k steps a day for 5 years now, and the only part of the shoe showing signs of wear is the rubber sole, which I had to glue back on.
Mobile games used to actually be decent before the advent of touch screen phones. Microtransactions were the final nail in the coffin though.