I have been using the 64 bit client since the day it was launched as a beta, and have never looked back. Not that I see my game executable reach over 3.5 GB or so often, but I have seen it gobble up as much as 6 GB in Minas Tirith.
(Unlike Cities Skylines with 20,000 custom steam workshop assets, which eats up 40+ GB of my 64 GB)
If people do have problems with the 64bit client, I would suggest to look at solving these issues. I cannot imagine anyone still running a 32-bit OS these days. Since 2010 or so, almost all new PC's were sold with 64 bit Windows (7 at the time) running. So that is not likely the issue. I think they said that about 0.1% of players still run a 32bit OS, or something like that on one of the Cordovan streams. Maybe a few Windows XP stragglers?
In any case, I doubt the OS is actually the issue, but I do understand people might have problems. What it is likely is your .ini configuration files, and it might be best to start with a fresh, vanilla config and re-do your favorite settings.
But yeah, 32-bit is on its way out in all respects. Apple has already completely killed it a few years ago, Windows still RUNS 32-bit programs for compatibility with older software, but Windows 11 no longer is delivered in a 32-bit version, and the only reason Windows 10 still had one was because they wanted it to run on a whole range of ultra-cheap tablets for the Indian and Chinese markets. But that too is way, way past obsolete now.
It is also much better for SSG to be able to focus on ONE client instead of TWO, which means engineers can do a wee bit more work on other things.
32-bit is dead. Long live 64-bit!
Moved from Riddermark to Arkenstone on 9/29/2015!
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Disclaimer: The definition of "Soon™" and "In The Near Future™" is based solely on SSG's interpretation of the words, and all similarities with dictionary definitions of the word "Soon™", "Near", and "Future" are purely coincidental and should not be interpreted as a time frame that will come to pass within a reasonable amount of time.