As a Nevadan, this is incorrect. Trump/NVGOP have lost every lawsuit they've filed save two:
1. One is being settled and allows a few more observers.
2. One was just filed and hasn't had a preliminary hearing.
There are no ongoing lawsuits in which there is judicial oversight of ballot counting.
The slowdown comes from two factors:
1. Approximately 60,000 statewide are "provisional" ballots. Nevada has same-day voter registration and those voters are allowed to cast provisional ballots. The provisional ballots are counted LAST. In order to count a provisional ballot the County Clerk must verify the voter's information with the Secretary of State to ensure that the voter did not cast a ballot in any other county. This is a very slow process.
2. The remaining ballots are mail-in ballots. Nevada law permits mail-in ballots to be counted if they are postmarked by Election Day and received through today, I believe. Pretty much all of the mail-in ballots remaining are in Clark County (Las Vegas). Due to the relatively short timeframe on implementing statewide mail-in voting, Clark County only has one signature matching machine. They're processing about 30k-50k votes per day which, to me, seems reasonable given the capital constraints.