Electra Protocol is a proof-of-stake blockchain. This means that the holders of XEP make sure that the network remains online. In order to give an incentive to XEP holders for keeping the network running, staking rewards are paid out.
The maximum amount of XEP coins currently listed is 30 billion XEP coins – and it not relevant for any proof-of-stake blockchain. More important is the yearly inflation rate at which the current supply is growing. The difference between the current supply and the maximum supply (30 billion XEP) is the amount which is available for staking right now (it is a theoretical number used in calculations). The max supply is not very much relevant for the Electra Protocol blockchain, given that the annual inflation rate of the protocol is just 3% XEP APY. Using the current XEP rewards mechanism, the max supply amount may be reached in the year 2050, 2060, or even later. If the 30 billion limit is reached, it will simply be crossed to pay for further staking rewards. This means that the annual inflation rate is determing when certain XEP supplies will be reached. This goes for other proof-of-stake projects as well.
More important than the max supply is the current supply: The amount of XEP coins in circulation is a lot less and is changing every day (you can check the current supply in the Block Explorer). At the time of writing it was 17,333,053,140 XEP (December 22, 2021). When coin burns take place with Electra Protocol, they are always deducting the current supply – and not the max supply.
Many other proof-of-stake blockchains use much higher staking rewards (12% APY, 18% APY, etc) which will result long-term in significant inflation rates and a loss of value over time to long-term holders. Additionally, many other crypto projects don’t have a max supply at all, causing them to indefinitely rise.