Realms Plus - Slow world processing

I purchased my own Realm a couple of months ago. And it has a lot of performance issues. For example, chunks are loaded very slowly: here is an example of a flight on Elithra (at this moment I was alone on the whole Realm):

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However, if I create the world locally on my computer, there are no such problems (screenshot of flying with maximum speed in creative):

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From this we can conclude that the problem lies in the performance allocated to each Realm owner. My purchase receipt says that up to 10 players can play simultaneously in this world. However, it is impossible to play here, even if I play with myself! Not to mention the cases when friends join me in the evening (in this situation, even the pistons on the farms work two to three times slower than usual). Is there a way to increase the performance allocated to each Realm? The current value is obviously insufficient.

P.S. Problems are also present in other places: sometimes it is impossible to eat food for some time (like here https://www.reddit.com/r/Minecraft/comments/cn7u5g/can_no_longer_pay_because_i_cant_eat/), sometimes (while digging) for seconds blocks are destroying without animation or sound, and then everything is abruptly replayed, as if the connection to the server was lost for a second. However, the source of all these problems is probably the same, and is described above.

Environment

App version: Minecraft for Windows 10 (v1.16.201)

Internet connection:  

Characteristics of my PC: