Should a time index be in ascending or descending order?

Planning some new tables, I am trying to decide whether an index should be "ascending" or "descending". The table will quite large (I imagine approx. 2000 inserts per minute, initially migrating from a different table with about 1 billion rows). I will be using timescaledb extension for this (for partitioning by time). This is how the table could be created:

create table "Sample"(
	"id" bigserial,
	"deviceId" int not null,
	"timestamp" timestamptz not null,
	"value" float8 not null
);
select create_hypertable('"Sample"', 'timestamp'); -- creates a desc index on "timestamp"

create index on "Sample"("deviceId", "timestamp"); -- should this be "desc"?

This is the two most common queries we'll be running (deviceId and timestamps may vary of course):

select "timestamp", "value"
from "Sample" where "deviceId"=123 and "timestamp"<'2024-01-01Z'
order by "timestamp" desc limit 1;

And

select "timestamp", "value"
from "Sample" where "deviceId"=123 and "timestamp" between '2024-01-01Z' and '2024-02-01Z'
order by "timestamp" asc;

So what I am trying to understand is in what order should the "timestamp" be? And why? My (probably wrong) intuition tells me that the index with "timestamp" should be in ascending order, because I need to order the data by timestamp in *ascending* order. But, the examples in the Timescale Documentation always index the time columns in descending order. I don't quite understand why. What is the ideal choice of indices here?