This is generally a good trade. Memory is not very useful (modulo filesystem caches) when you're not using it, and has a very low cost when you are (extremely tiny power consumption). CPU cycles cost power (leading to heat dissipation and battery life loss) when you use any amount, and latency when you use too much. Latency directly affects user experience and efficiency, which is a much higher cost than "my RAM is at 75% usage".
Additionally, Chrome's tradeoff is such that it works out better on cheaper devices. Memory is far cheaper than more powerful processors - which also reduce battery life, which is even more expensive. On more expensive devices, you have all the memory you need for Chrome anyway, so you're just getting better latency.
Finally, there are very few cases where you should have a large number of Chrome tabs open anyway. Multi-tasking is impossible (the human brain simply doesn't support it) and rapid context-switches are inefficient. As much fun as it might be to have 5 tabs open on each of 10 different topics, you're simply decreasing your productivity and capacity for focus. Even when doing multi-disciplinary research, there are a ton of ways to get around the problem of running out of memory due to Chrome tabs: printing pages to PDF, turning off JavaScript, downloading research papers and reading them in a native PDF viewer, extracting content from webpages and inserting into local documents, and the classic using darn bookmarks instead of tabs like they were intended to be used.
(of course, in an ideal world, all web browsers would use absolutely no memory or processing power whatsoever - I'm just defending this particular engineering tradeoff)