It depends on how you use it. Size matters. On a site I manage, we send about 64KB of JavaScript and we are working to make that smaller... and the main site functionality works when JavaScript is disabled.
In contrast, many sites seem to think that 1MB of JavaScript, or even 5MB, are acceptable, and they can't even show simple static content when client-side JavaScript is disabled. On a slow link, 1MB of JavaScript means that the user has probably given up. And it's not just the size. 200KB of HTML is farfar faster than 200KB of JavaScript; web browsers are highly optimized for handling HTML, while processing JavaScript is necessarily much slower. JavaScript is great for some things, but like a sledgehammer it's not always the best solution. Too many people aren't considering the real end-user experience. "Pretty graphics, but it takes 5 minutes to download" is usually not a worthwhile tradeoff.
To paraphrase Goldblum:
Your web designers were so preoccupied with whether or not they could use JavaScript, they didn’t stop to think if they should.
In contrast, many sites seem to think that 1MB of JavaScript, or even 5MB, are acceptable, and they can't even show simple static content when client-side JavaScript is disabled. On a slow link, 1MB of JavaScript means that the user has probably given up. And it's not just the size. 200KB of HTML is far far faster than 200KB of JavaScript; web browsers are highly optimized for handling HTML, while processing JavaScript is necessarily much slower. JavaScript is great for some things, but like a sledgehammer it's not always the best solution. Too many people aren't considering the real end-user experience. "Pretty graphics, but it takes 5 minutes to download" is usually not a worthwhile tradeoff.
To paraphrase Goldblum:
Your web designers were so preoccupied with whether or not they could use JavaScript, they didn’t stop to think if they should.