Q about some of the limits in products/categories/tags etc at Open Cart?

Hello community!
We're starting a new big (very big) online store and looking for a new e-commerce platform. OpenCart is one of our candidates.
We have a pretty clear list of requirements to the platform. Simple google search shows minimal to no answers, so I'm asking the community and Opencart experts to help us.

1. Any limits in categories qty? (e.g. shopify has a limit of 5k, that is totally not for us) About 50k may be needed for our store.
2. limit of max products amount (reasonable limit, considering a need of a store to perform/load fast)
3. Limit of products can be added daily/monthly etc?
4. What import/export speeds we can expect? (ignoring the hosting limits, we will go with a top-notch providers) How much time usually required to import 100k products, with / w/o images?
5. If you guys know other limits / restrictions, please let us know - like max tags amount per product, max filters visible in the category, etc.

Well, you obviously plan to create something very impressive, but to save
costly time, you probably expect free Consulting on how to create the ultimate
Solution, to eventually enable you, to decide on using OpenCart.
You most likely just ignored, that, in contrary to other Software, like WP, Opencart
only serves one single purpose, and that makes every NEW OC Forum Participant
to be a new potential Competitor as well, by Nature of (Internet) things.

So, better don't rely on this Forum, when it comes to such Information, 'regular'
OC Users won't be around in Numbers, to assist others for free, and most DEV's
are here, to frequently generate some Cash out of their presence and frequent
free assistance, when it comes to solve certain Problems on existing things, and
as long it's NOT about commercially offered Extensions/Themes.

Still, Lots of information exists on OpenCart, and it's Options, Functions, whatever... ,
just search Google, to find Answers on just about everything possible. Even OC
has a (fairly simple) Explanation on such:
https://www.opencart.com/index.php?route=cms/feature

Just to bring you back on Earth, many expect free Heaven, and end up in
Frustration, but if you do not expect more, than you would eventually be
willing to share here with potential Competitors , you won't disappointed ...
Good Luck!
Ernie

1. Any limits in categories qty? (e.g. shopify has a limit of 5k, that is totally not for us) About 50k may be needed for our store.

No limit, only server limits apply

2. limit of max products amount (reasonable limit, considering a need of a store to perform/load fast)

No limit, only server limits apply

3. Limit of products can be added daily/monthly etc?

No limit, only server limits apply and how fast you can type

4. What import/export speeds we can expect? (ignoring the hosting limits, we will go with a top-notch providers) How much time usually required to import 100k products, with / w/o images?

impossible to answer depends on:
size of your import, your upload speed, server and database speed

5. If you guys know other limits / restrictions, please let us know - like max tags amount per product, max filters visible in the category, etc.

No limit, only server limits apply