Spoiler tags are not very accessible on mobile platforms.
Works fine on my tablet and my phone, one tap and the spoiler text appears. If spoiler tags are broken on any of the supported browsers, we should collect detailed information on where they are broken and ask SE to fix that.
Spoiler tags get in the way of search engines.
They're just some CSS, search engines don't even notice them
Putting answers at the fingertips of googlers is the main way we make
the internet a better place to be and are no justification to have
posts like this or this.
True, and I agree that there is a significant conflict between useful titles and spoiler-free titles.
If you are a user and don't want to be spoiled about a game you can
put it in your ignored tags list.
This is something the very active users here know, but the option to completely hide ignored posts is absolutely not obvious and I bet that most casual SE users don't even know they can do that. If we decide to stop caring about putting major spoilers in titles, the way to avoid them has to be far more obvious or we'll annoy a lot of users.
I agree that there is no point in spoiler-tagging answers to questions that assume that there will be spoilers, unless you spoil more that one can reasonably expect from the question.
Spoiler markup in a clearly spoilery question is often necessary to prevent spoilers from being visible in the question excerpt. Don't know if there is a better way to do that.
Titles are an entirely different problem, and I think we should put some effort into trying to keep them free from major spoilers. Even ignoring and hiding questions won't save you in all cases, they'll still appear in title suggestions when asking questions or in the list of related questions in the sidebar. They also appear in the question feed on the Bridge. I don't like how that often mutilates the title, but I now tend towards favoring avoiding major spoilers in titles at the price of having bad and hard to find titles.
To be clear, I'm only talking about major spoilers, significant plot twists or posts about the game ending. Anyone who wants to avoid even minor spoilers has to stay off the internet until they finished a game anyway.
There might also be some technical solutions that could help with this, but everything I can come up with would be complicated enough that I doubt SE would ever implement it. I think I proposed in the past something like being able to spoiler-tag titles, but that's also a rather ugly solution. Something like being able to indicate that you don't care about spoilers in some tag could minimize the annoyance of the spoiler tags, but that would be a per-user preference and SE is well known for absolutely hating those.
On the topic of spoilers in titles, we should have a clear decision. Either we allow them clearly and make sure everyone know to ignore tags if they don't want to get spoilers, or we do our best to avoid major spoilers in titles. Anything in between is madness.