PowerBI Refresh - Single table vs Multiple tables

I have a question with respect to the Power BI refresh timings.

I have a table (Table 1) which has got about 1.9 billion records and there are no relationships in this table. This is the only table that is present in Delta Tables using ADBX.

While I have another table (Table 2) with about 40 GB of data at 8.5 billion records which is connected in a relationship with two other tables each having about 1.8 GB each.

I have created incremental partitions on both the tables. And this have been implemented using tabular Editor's "Apply Refresh Policy".

The refresh of Table 1 which has about 1.9 billion records takes about 2 hours to process, however the refresh of a table (Table 2) having multi partitions with the granularity at day level with about 1.6 billion records fails. I am refreshing data for a particular month alone. I am using XMLA Endpoint to accomplish the refresh.

However if I process Table 2 in groups of 4 to 5 partitions upto 8 partitions, the table successfully refreshes without any issues.

So would it be okay to say that if a table has multiple relationships and a refresh is set up the refresh timings would be slower compared to the table with no relationships?

Thanks