Sorry, I’m wrong. Growth will not be exponential, BUT a one time block size increase to 10MB, and with current Bitcoin on-chain usage keeping those blocks full, would make each node process 10 times the data, and make it “feel” exponential.
“feel” exponential - this is something new in cost estimation. 
My computer, bought 5 years ago, processes a new block in less than 1 second. a 10mb block will process less than 10 seconds. And blocks appear once every 10 minutes. The only expense is disk space. At 10MB block - 0.5 TB per year. 2tb. hard disk ~$ 60 and this is for 4 years. The cost per year is $ 15, per month ~ $ 1.2. And now that I make a modest 12 transactions a year, look at the size of the average fee, and estimate how much I have costs due to 1MB. block.
You understand that it is your "concern" for the user that only brings them extra costs.
Even if we take the more expensive option, together hdd ssd. 2tb ssd - ~ $ 240. Divide by 48 months - $ 5 per month. The fee for one transaction per month is about the same level, and I will not pay this fee. That is, I will be at the same level in terms of costs. But in return, I get a 10-fold increase in the Bitcoin system. (10x! , Karl).
Your computer is not other people’s computers. Plus the real problem is also bandwidth, and latency remember? The Initial Blockchain Download has become more and more difficult.
You want real scaling, solutions like this is real scaling, https://medium.com/mit-media-lab-digital-currency-initiative/utreexo-demonstration-release-a0d87506fd70
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I want to see Bitcoin Cash’s blocks full, everyday, for a whole year.
You are more careful with your desires. If the Bitcoin Cache develops to the point that users will make 2.5 million transactions a day, and bitcoin will remain at its 350 thousand, then I do not think that this is a a good outcome for Bitcoin..
Increasing transaction throughput, but centralizing the validators is not real scaling.