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If you were questioning, if Bitcoin core (BTC) is suffering from scaling problems, why not just raise the blocksize limit from 1 MB to a higher number like Bitcoin Cash (BCH)?

Well, BTC users will say to you, that 1 MB limit is necessary to keep the network decentralized, because if there were bigger blocks, less people would be able to run a full node, so the purpose of Bitcoin of being a decentralized network would be destroyed.

Today BTC have a blocksize limit of 1 MB, and BCH have a 32 MB limit, both have a time target of 1 block every 10 minutes.

This have a bit of true, but BTC users are exaggerating the effects of bigger blocks, bigger blocks will not destroy decentralization, here is the resources needed to run a full node:

CPU power

CPU power is necessary to process the transactions, BTC users will say that with small blocks, even a potato computer can be a full node, but potatos are much more powerful than you think. A Raspberry Pi 4 can validate 256 MB blocks without any problems.

A Raspberry Pi 4 have a 4 core CPU, with a 1.5 GHZ clock speed, wich is basically a CPU from cheap mobile phone and as time passes, hardware gets more powerful at the same price, there is even a unofficial roadmap to a Raspberry Pi of 2033 to support 1 TB blocks!

Bandwidth

Bandwidth is necessary to nodes broadcast the transactions and blocks on the network, first you need to understand how a transaction is broadcast and confirmed by the network.

1. User sends a transaction.

2. Nodes that are near receive this transaction,

3. These near nodes broadcast the transaction to other nodes.

4. All nodes will store this transaction in their memory, the mempool is all transactions that are pending.

5. Miners will include this transaction in their blocks, and mine it.

6. The miner wich mines a valid block first, will broadcast the block to the network, nodes will check the transactions on the block, and update their copy of the blockchain.

If you noticed, the transaction needs to be broadcasted 2 times, now lets do the math with 32 MB blocks wich are created every 10 minutes:

32 * 2 = 64 MB, wich will need to be converted to bits, so 512 Mb. ( a quick note, storage is meansured in Bytes, and bandwidth is meansured in bits, 1 Byte = 8 bits, MB is megabytes, Mb is megabits.)

there are 600 seconds in 10 minutes, so 512/600 = 0,853 Mb/s, a full BCH block today needs of 853 Kb/s of bandwidth to be broadcasted, so even people with a slower internet can run a full node, i live in South America, and i have 20 Mb/s of bandwidth available, as with hardware, bandwidth gets faster as time passes, not a problem.

Also BCH have a technology called Xthinner, wich reduces theusage of bandwidth when broadcasting blocks.

Storage

Full nodes needs to store the ledge, so here is how much space is necessary to store 32 MB blocks for every year.

There are 6 blocks every hour, 24 hours per day and 365 days per year: 32 * 6 * 24 * 365 = 1,681,920 MB per year, or 1.68 TB.

How much this would cost? You need at least a 120 GB SSD to read the new transactions, and a big HDD to store the old transactions.

A 5 TB HDD costs about $100 today, wich is $20 per TB, or $33.6 per year + a $25 SSD for hot storage. (Source: Amazon).

Plus, only archival nodes need to store the full ledge, most full nodes only need to store some newer blocks, and then store only the header of older blocks, wich can be stored in a few GB. (See the section 7 of the Bitcoin whitepaper: Reclaming Disk Space

Conclusion

Even if the 32 MB blocks were full today, running a full node would not be expensive, ensuring decentralization, so Bitcoin Cash can scale safely.