At what point does WotC have to continually hold the hand of every player who can't be bothered to read the rules, who then get into arguments with their DM because the DM is daring to include rules from the DMG in a game that they specifically are running?
Heck... I've seen posts here in all these threads with players making comments about these new rules they don't think work or make sense... only for someone to point out "Uh... this gets mentioned and referenced here." Even here people can't be bothered to read the rules! So why should WotC waste time, space, energy, and money adding more and more redundant mentions of rules all over the place just trying to baby-proof them for those people? If you can't be bothered to read the rules... then too bad when the DM "springs" something on you. That ain't the DM's problem, and it certainly isn't WotC's problem.
Enough that the only place it shows up isn't buried in the introduction?
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second full paragraph on page 6 of the PHB
If the player misses that to get to the good stuff...
In Chapter 1, for example, when it runs through making a character, unless I missed it, it doesn't seem to imply at any point that the DM might have some restrictions on what races or classes are out there. It is all about the player choosing any options they want and "What’s important is that you come to the table with a character you’re excited to play."
It does note the DM might decide to have you begin at a higher level. It mentions that there is a standard array and the variant of point buy as options beyond the rolling, but leaves it entirely to the player if they roll or standard, and that they have a third choice of the point buy if the DM lets them have that as a third option. For backgrounds it explicitly says the DM might offer additional backgrounds or work with you on one, but never hints they might restrict them.
In Chapter Two, it doesn't mention that the DM might restrict what races are available - except that you should ask permission to play a Drow.
Chapter Three says the twelve classes "are found in almost every D&D world", but doesn't say how one knows if they are or not.
etc...
One extra sentence or tiny box to start each of those three chapters doesn't feel awful to me or like it's asking WotC to put in extraordinary effort.
Edit: Or I'd even take them putting some sort of emphasis around it in the introduction I guess, instead of it just sitting there as part of a wall of text.
