If you want to read over my first comment, it says that OP should consider the commitment of a puppy and that they are not able to do all the things an adult dog does immediately. It doesn't say they absolutely shouldn't get a puppy. It is their first dog on their own and is not something that should be taken lightly. In addition I literally called the chart a baseline. For a new dog owner, it's a good guideline.

Again, waiting until a year for hikes or other strenuous exercise is backed up by science and most modern vets will tell you the same thing. Yes, you could go for long hikes at 6 months, and it could of course be totally fine, but that does not mean it is the safest or best practice.

There are numerous threads on this subreddit arguing the exact same point. The consensus is that puppies should not hike. It is not good for their growth and overall health.