That's certainly true, mate. Bitcoin Cash will become extremely centralized as it increases its block size to 32mb on May 15th. This will allow less nodes to become available on the network, as storage and bandwidth costs will increase. The blockchain will increase up to 32x than Bitcoin Core. Therefore, people would prefer to run Lightning nodes and Core nodes as costs will be cheaper in the long run.
Before we know it, nobody would want to run a Bitcoin Cash node as it'll be very expensive to do so. On the other hand, Bitcoin Core and Lightning nodes will be highly accessible allowing anyone to join the network without spending a lot of money. In the end, Bitcoin with its Lightning Network scalability solution, would prevail over most cryptocurrencies we know and love today.

There seems to be some confusion about their block size increase.
They are increasing the
Potential of a block to be 32mb, not that every block will always be 32 MB.
In Fact, they have only rarely used the 8mb blocks since they began, only when someone tried to spam transaction them , and they wipe it out in 1 block.
https://cash.coin.dance/blocksThe Bitcoin (BTC) chain has grown 32.77GB more than the Bitcoin Cash blockchain.
It is currently 6.7% more profitable to mine on the Bitcoin (BTC) chain.?
It is currently 21.52x more expensive to transact on the Bitcoin (BTC) network in USD.
As you can see the Bitcoin Core Blockchain is ~33GB bigger now than the Bitcoin Cash Blockchain.
Bitcoin Cash just raised the upper limit possible so they have no fear of transactions congestion for years to come.
Bitcoin Core was congested for many months with insanely high fees, Bitcoin Cash will not have to worry about it.
As you can see here :
https://www.blocktrail.com/BCCBitcoin Cash is using on average less than 100kb per block, so the fact it is taking less resources to run than Bitcoin Core.
So the worry that Bitcoin Cash will be more expensive to run is a pure Myth at the present time.
Considering a Bitcoin Cash node only has to run a full node to help the network , and that a Bitcoin Core Node and a LN Hub would be required for a stable LN network, it may turn out core full node and LN hub data & definitely bandwidth requirements would exceed anything needed by just running a simple Bitcoin Cash Node.

But Time will tell on that speculation.
* The Bandwidth requirements will be much greater for Bitcoin Core's LN Hubs, the reason is if you ddos LN hubs at the time channels are scheduled to be closed,
it opens the possibility of one of the parties stealing the others coins, this attack vector is not possible on Bitcoin Cash Full Nodes so they will need less ddos protections.*The average U.S. fixed broadband download speed was 64.17 Mbps (15th in the world) in the first half of 2017,
while the average upload speed was 22.79 Mbps (24th in the world), according to data released today from internet speed test company Ookla.Sep 7, 2017
Taking the lowest average upload speed of 22.79 Mbps / 8 = 2.85 MB per second
So a 32MB file would be Relayed / Transferred in less than 12 seconds
0 Block Generated -1 Node
12 seconds - 2 Nodes
24 seconds - 4 Nodes
36 seconds - 8 Nodes
48 seconds - 16 Nodes
60 seconds - 32 Nodes
72 seconds - 64 Nodes
84 seconds - 128 Nodes
96 seconds - 256 Nodes
108 seconds - 512 Nodes
120 seconds - 1024 Nodes
132 seconds - 2048 Nodes
144 seconds - 4096 Nodes
156 seconds - 8192 Nodes
168 seconds - 16384 Nodes
180 seconds - 32768 Nodes
* All of this happens within 3 minutes, the fact is some will be running 1 gigabit or higher bandwidth nodes and they will increase the propagation at a much faster rate than above. *
* Essentially the 32MB blocks are no big deal even at today's average internet speeds.*