If someone was getting into Product Management today, what resources would you point them towards, so that they have a toolkit and understand the job? 

ie The Lean Startup. Jobs to Be Done.

Here are a few hundred posts on a variety of product topics: https://www.mvwi.co/writing/product-resources

A little dated now, perhaps, but the bits that are still around are also the bits worth reading

The most valuable advice I can give beyond these^ is that product is an apprenticeship skill — the biggest determinant of how quickly you learn is who you're learning from so tell whoever is asking to choose their peer group well

✨ Be the training data you want to see in the world ✨ | DΞF | Head of Product Serotonin | building se.ro

Same. Though I think the skills become more valuable at large.

I'm not sure, my reading diet has shifted away from product and more towards the products themselves but that could also just be the natural progression of doing this for a while

I honestly think that 3/4 of product jobs are going to go away in the next ~10 years

This is great. Do people just not write about product anymore? Maybe the role has just gotten that mature.