I think keeping it to one page shows respect for a reader's time. Instead of dumping everything I can think of onto the page and letting them pick through it for what's important, I do that work for them. In many cases I've customized the résumé to some extent for the employer.
I've never had anyone tell me it was too short.
A well-laid out resume does this for the reader. Basically, the reader should be able to get a high-level idea of the applicant by quickly reading the top of each section/subsection, and then dig deeper into whatever they feel is relevant by moving deeper into the "tree".
Anecdotally, when I interview senior level people (data scientists, but this would apply to software engineers too), more than half the resumes are two pages. It's not abnormal and by no means a deal-killer. The last guy I interviewed had seven jobs and three degrees crammed into a single page - I had to waste 25% of the interview just asking him what he did at each job because his resume didn't tell me (except a title and a really terse summary). This only hurt him because I had less time to build a case to hire him.
But regarding your question, I think two pages is perfectly fine in the tech world, if you have enough to say. By the time you're ten years into a career I'd be surprised if you don't want more than a page to talk about what you know and what you've done. I think the aesthetic gains from a one page resume aren't worth the risk of omitting something that's important to a potential employer. It's the four page resumes that annoy me.