It depends. I'm still under 40, and many of the things he considers mistakes I don't (yet). That said, three of the things on the list I've been able to avoid, and I think it's made the rest easier. 1. I was lucky to get a bunch of money early, and stopped spending a lot of time writing grants after the first year. 2. Made a conscious decision to not travel excessively, spend time at home, and vacation for all sorts of family reasons. That said, I've used twitter to supplement the backroom chatter I am missing and that's worked well enough 3. I initially took a lot of committee work but have backed off a ton in the last few years.
I do run a pretty big group, though I've downsized a bit (now 8 Phd, 3 postdocs, many undergrads). We work on too many things and most are pretty ambitious, but that makes it fun. I wouldn't change that much honestly. Maybe I need a few more years before I regret everything, but things are pretty good IMO, but again, I think you need a few chips to fall your way before things become manageable (e.g., like early grants).
Yes, it really depends on the field. That said in the last 5 or so years there are a lot of early investigator pools of money in biology. This is not true for everyone, but the hard years everyone talks about now is mid-career. I'm not there yet, but I'm starting to see how it gets a lot more difficult.
Getting a research grant is not "hitting the lottery", it's being recognized for your previous work and having people believe that your new proposals make sense and that you have what it takes to carry on your new ambitions.
I do run a pretty big group, though I've downsized a bit (now 8 Phd, 3 postdocs, many undergrads). We work on too many things and most are pretty ambitious, but that makes it fun. I wouldn't change that much honestly. Maybe I need a few more years before I regret everything, but things are pretty good IMO, but again, I think you need a few chips to fall your way before things become manageable (e.g., like early grants).