I disagree. To start, 5G already has 5x the amount of spectrum as 4G (100MHz vs 20MHz). So we would minimally see 5x the speed on 5G compared to 4G. However, with other advancements at the radio level like 256QAM and OFDMA, the benefits are multiplied further.
Of course 5G will become more congested as more users onboard. But it will be far from as bad as 4G because 5G is designed to carry more users in the same spectrum, and we also have so much more spectrum.
Also 4G didn't slow down as more users got onboard because IMDA eventually released more spectrum (and refarmed from 3G). 4G slowed down because we stopped paying $80 for 4GB of data and started paying $20 for 100GB of data (thank you SIMBA).
You may be a bit (too) obsessed with front end radio paper specs. Haha..
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No matter how much new technologies goes into the front end 5G SA/NR radio base stations or client devices -- the high 5G SA/NR bandwidth comes at a cost of range.
5G SA/NR range is (much) shorter than 4G -- so REAL LIFE bandwidth drops much faster or drops much more -- when people/users moves a bit further away.
All the paper specs high number 5G SA/NR bandwidth -- assumes quite ideal conditions (as if all 5G users will be always be VERY VERY close to 5G base stations).
Real life is not ideal & the average real life bandwidth -- by the time everybody is on 5G SA/NR -- will be MUCH LOWER than paper specs in real world conditions.
We will know in 5-10yrs time.
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You're also missing out / NOT CONSIDERING a VERY IMPORTANT factor -- that nobody talks about.
No matter how much technologies goes into the front end 5G SA/NR radio base stations or client devices -- it
CANNOT OVERCOME another important factor.
That factor is:
Backhaul bandwidth limit of the mobile data network (at any particular location).
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Will stop here -- since digressing from this thread's main topic. Haha..