I'd disagree in the point in bold. 34(front)/32(rear) is pretty much the standard bottom gear on most off the shelf road bikes these days(50/34 11-32). That or 34/34. I wouldn't describe it as very, very low. It's not exotically low like the gears you can get with a triple or on some gravel 1x setups. That's just me being picky about "very, very low". It's not all that relevant to the thread.
That said, we're all different and it's up to the OP to sort out their own gearing.
I made a lot of use of Tacx virtual climbs preparing for my visit to the Grand Colombier last year. That was a totally different trip as it was one day riding not multiple, but I would say that the virtual rides are pretty realistic in terms of what it takes physically, except they don't simulate very steep sections very well, especially not if you are heavier than average (as I am). My legs felt similar at the to of the real one to how the felt at the "top" of a pretend one.