I'm not the parent, but I do web development - here's how I understand it:
> hard for end users to customise
I think, he means that a css-based ("modern") solution would allow end-users to just swap the css (a feature most web-browsers have as a built-in) to change the site's appearance - whereas you cannot change the way a <table> looks, for example. That is, you can't easily make <table> columns appear below each other, for example.
> works terribly in any other context than a desktop browser
The parent probably means modern non-desktop web browsers, i.e. ones with javascript and media-query support. Using media queries would allow automatically changing the site's appearance to something more usable for small-screen devices (for example) - by using bigger buttons/links/up-vote-triangles or something like that.
The problems you mentioned are orthogonal to that - mostly caused by devs that only target js-enabled modern browsers. That's bad, of course, but it's not part of "modern web development" per se - it's just bad web development.
> plays terribly with all other web tooling
If you use "modern" web-dev methods (that is, styling only per css), other (web-)services that display your site in different contexts (think google reader or desktop mail readers or something like that) can swap or remove the css and get the content (including semantics like "headline", "list" and so on) without the styling ("these are table columns", "this is centered"). In theory, at least.
I don't understand the rest of the points either, to be honest. <center> and <table> are very compact, compared to equivalent HTML/CSS solutions - that's part of the reason why people keep using them.
> hard for end users to customise
I think, he means that a css-based ("modern") solution would allow end-users to just swap the css (a feature most web-browsers have as a built-in) to change the site's appearance - whereas you cannot change the way a <table> looks, for example. That is, you can't easily make <table> columns appear below each other, for example.
> works terribly in any other context than a desktop browser
The parent probably means modern non-desktop web browsers, i.e. ones with javascript and media-query support. Using media queries would allow automatically changing the site's appearance to something more usable for small-screen devices (for example) - by using bigger buttons/links/up-vote-triangles or something like that.
The problems you mentioned are orthogonal to that - mostly caused by devs that only target js-enabled modern browsers. That's bad, of course, but it's not part of "modern web development" per se - it's just bad web development.
> plays terribly with all other web tooling
If you use "modern" web-dev methods (that is, styling only per css), other (web-)services that display your site in different contexts (think google reader or desktop mail readers or something like that) can swap or remove the css and get the content (including semantics like "headline", "list" and so on) without the styling ("these are table columns", "this is centered"). In theory, at least.
I don't understand the rest of the points either, to be honest. <center> and <table> are very compact, compared to equivalent HTML/CSS solutions - that's part of the reason why people keep using them.